147-619: See text Synechococcus (from the Greek synechos , in succession, and the Greek kokkos , granule) is a unicellular cyanobacterium that is very widespread in the marine environment . Its size varies from 0.8 to 1.5 μm . The photosynthetic coccoid cells are preferentially found in well–lit surface waters where it can be very abundant (generally 1,000 to 200,000 cells per ml). Many freshwater species of Synechococcus have also been described. The genome of S. elongatus strain PCC7002 has
294-433: A 2021 study on the cyanobacterium Synechocystis . These use a set of genes that regulate the production and export of sulphated polysaccharides , chains of sugar molecules modified with sulphate groups that can often be found in marine algae and animal tissue. Many bacteria generate extracellular polysaccharides, but sulphated ones have only been seen in cyanobacteria. In Synechocystis these sulphated polysaccharide help
441-405: A central state apparatus designed to manage state institutions more efficiently. These changes helped Texas universities receive federal research funds. Beginning around the mid-20th century, Texas began to transform from a rural and agricultural state to one urban and industrialized. The state's population grew quickly during this period, with large levels of migration from outside the state. As
588-417: A cyanobacterial species that does so is Microcoleus vaginatus . M. vaginatus stabilizes soil using a polysaccharide sheath that binds to sand particles and absorbs water. M. vaginatus also makes a significant contribution to the cohesion of biological soil crust . Some of these organisms contribute significantly to global ecology and the oxygen cycle . The tiny marine cyanobacterium Prochlorococcus
735-458: A fact that may be responsible for their evolutionary and ecological success. The water-oxidizing photosynthesis is accomplished by coupling the activity of photosystem (PS) II and I ( Z-scheme ). In contrast to green sulfur bacteria which only use one photosystem, the use of water as an electron donor is energetically demanding, requiring two photosystems. Attached to the thylakoid membrane, phycobilisomes act as light-harvesting antennae for
882-568: A frontier territory. The state became notorious as a haven for people from other parts of the country who wanted to escape debt, war tensions, or other problems. "Gone to Texas" was a common expression for those fleeing the law in other states. Nevertheless, the state also attracted many businessmen and other settlers with more legitimate interests. The cattle industry continued to thrive, though it gradually became less profitable. Cotton and lumber became major industries creating new economic booms in various regions. Railroad networks grew rapidly as did
1029-411: A key role in developmental processes, such as akinete and heterocyst differentiation, as well as strategy for population survival. Cyanophages are viruses that infect cyanobacteria. Cyanophages can be found in both freshwater and marine environments. Marine and freshwater cyanophages have icosahedral heads, which contain double-stranded DNA, attached to a tail by connector proteins. The size of
1176-514: A major destination for migration during the early 21st century and was named the most popular state to move for three consecutive years. Another study in 2019 determined Texas's growth rate at 1,000 people per day. During the COVID-19 pandemic in Texas , the first confirmed case of the virus in Texas was announced on March 4, 2020. On April 27, 2020, Governor Greg Abbott announced phase one of re-opening
1323-529: A part of the Sun Belt , Texas experienced strong economic growth, particularly during the 1970s and early 1980s. Texas's economy diversified, lessening its reliance on the petroleum industry . By 1990, Hispanics and Latino Americans overtook Blacks to become the largest minority group. Texas has the largest Black population with over 3.9 million. During the late 20th century, the Republican Party replaced
1470-552: A process where the energy of light is used to synthesize organic compounds from carbon dioxide. Because they are aquatic organisms, they typically employ several strategies which are collectively known as a "CO 2 concentrating mechanism" to aid in the acquisition of inorganic carbon (CO 2 or bicarbonate ). Among the more specific strategies is the widespread prevalence of the bacterial microcompartments known as carboxysomes , which co-operate with active transporters of CO 2 and bicarbonate, in order to accumulate bicarbonate into
1617-442: A proposed model of microbial distribution, spatial organization, carbon and O 2 cycling in clumps and adjacent areas. (a) Clumps contain denser cyanobacterial filaments and heterotrophic microbes. The initial differences in density depend on cyanobacterial motility and can be established over short timescales. Darker blue color outside of the clump indicates higher oxygen concentrations in areas adjacent to clumps. Oxic media increase
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#17330845527611764-412: A range of toxins known as cyanotoxins that can cause harmful health effects in humans and animals. Cyanobacteria are a very large and diverse phylum of photosynthetic prokaryotes . They are defined by their unique combination of pigments and their ability to perform oxygenic photosynthesis . They often live in colonial aggregates that can take on a multitude of forms. Of particular interest are
1911-559: A response to biotic and abiotic stresses. However, cell death research in cyanobacteria is a relatively young field and understanding of the underlying mechanisms and molecular machinery underpinning this fundamental process remains largely elusive. However, reports on cell death of marine and freshwater cyanobacteria indicate this process has major implications for the ecology of microbial communities/ Different forms of cell demise have been observed in cyanobacteria under several stressful conditions, and cell death has been suggested to play
2058-488: A serious threat to aquatic environments and public health, and are increasing in frequency and magnitude globally. Cyanobacteria are ubiquitous in marine environments and play important roles as primary producers . They are part of the marine phytoplankton , which currently contributes almost half of the Earth's total primary production. About 25% of the global marine primary production is contributed by cyanobacteria. Within
2205-478: A single plane and lack sheaths". This definition of the genus Synechococcus contained organisms of considerable genetic diversity and was later subdivided into subgroups based on the presence of the accessory pigment phycoerythrin . The marine forms of Synechococcus are coccoid cells between 0.6 and 1.6 μm in size. They are Gram-negative cells with highly structured cell walls that may contain projections on their surface. Electron microscopy frequently reveals
2352-474: A size of 3.4 M bp , whereas the oceanic strain WH8102 has a genome of size 2.4 Mbp. Synechococcus is one of the most important components of the prokaryotic autotrophic picoplankton in the temperate to tropical oceans. The genus was first described in 1979, and was originally defined to include "small unicellular cyanobacteria with ovoid to cylindrical cells that reproduce by binary traverse fission in
2499-446: A sole nitrogen source. Marine Synechococcus species are traditionally not thought to fix nitrogen. In the last decade, several strains of Synechococcus elongatus have been produced in laboratory environments to include the fastest growing cyanobacteria to date, Synechococcus elongatus UTEX 2973. S. elongatus UTEX 2973 is a mutant hybrid from UTEX 625 and is most closely related to S. elongatus PCC 7942 with 99.8% similarity. It has
2646-613: A supply state was marginalized in mid-1863 after the Union capture of the Mississippi River . The final battle of the Civil War was fought at Palmito Ranch , near Brownsville, Texas, and saw a Confederate victory. Texas descended into anarchy for two months between the surrender of the Army of Northern Virginia and the assumption of authority by Union General Gordon Granger . Violence marked
2793-500: A symbiotic relationship with plants or lichen -forming fungi (as in the lichen genus Peltigera ). Cyanobacteria are globally widespread photosynthetic prokaryotes and are major contributors to global biogeochemical cycles . They are the only oxygenic photosynthetic prokaryotes, and prosper in diverse and extreme habitats. They are among the oldest organisms on Earth with fossil records dating back at least 2.1 billion years. Since then, cyanobacteria have been essential players in
2940-435: A third of Colorado , and small portions of Kansas , Oklahoma , and Wyoming to the federal government, in return for the assumption of $ 10 million of the old republic's debt. Post-war Texas grew rapidly as migrants poured into the cotton lands of the state. They also brought or purchased enslaved African Americans, whose numbers tripled in the state from 1850 to 1860, from 58,000 to 182,566. Texas re-entered war following
3087-419: A waving motion; the filament oscillates back and forth. In water columns, some cyanobacteria float by forming gas vesicles , as in archaea . These vesicles are not organelles as such. They are not bounded by lipid membranes , but by a protein sheath. Some cyanobacteria can fix atmospheric nitrogen in anaerobic conditions by means of specialized cells called heterocysts . Heterocysts may also form under
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#17330845527613234-408: A weaker cell in a filament, called a necridium. Some filamentous species can differentiate into several different cell types: Each individual cell (each single cyanobacterium) typically has a thick, gelatinous cell wall . They lack flagella , but hormogonia of some species can move about by gliding along surfaces. Many of the multicellular filamentous forms of Oscillatoria are capable of
3381-578: A wide range of cyanobacteria and are key regulators of the cyanobacterial populations in aquatic environments, and may aid in the prevention of cyanobacterial blooms in freshwater and marine ecosystems. These blooms can pose a danger to humans and other animals, particularly in eutrophic freshwater lakes. Infection by these viruses is highly prevalent in cells belonging to Synechococcus spp. in marine environments, where up to 5% of cells belonging to marine cyanobacterial cells have been reported to contain mature phage particles. The first cyanophage, LPP-1 ,
3528-417: Is a way for the cells to maximize the use of available light for photosynthesis. A few genera lack phycobilisomes and have chlorophyll b instead ( Prochloron , Prochlorococcus , Prochlorothrix ). These were originally grouped together as the prochlorophytes or chloroxybacteria, but appear to have developed in several different lines of cyanobacteria. For this reason, they are now considered as part of
3675-516: Is characterized by low salt tolerance. Cells are obligate photoautrotrophs, lack phycoerythrin, and are thermophilic. The reference strain PCC6715 was isolated from a hot spring in Yellowstone National Park . Cluster 3 includes phycoerythrin-lacking marine Synechococcus species that are euryhaline , i.e. capable of growth in both marine and freshwater environments. Several strains, including
3822-473: Is estimated 10% of all photosynthesis on earth is carried out with viral genes. Not all viruses immediately kill their hosts, ' temperate ' viruses co-exist with their host until stresses or nearing end of natural life span make them switch their host to virus production; if a mutation occurs that stops this final step, the host can carry the virus genes with no ill effects. And if a healthy host reproduces while infectious, its offspring can be infectious as well. It
3969-728: Is favoured in ponds and lakes where waters are calm and have little turbulent mixing. Their lifecycles are disrupted when the water naturally or artificially mixes from churning currents caused by the flowing water of streams or the churning water of fountains. For this reason blooms of cyanobacteria seldom occur in rivers unless the water is flowing slowly. Growth is also favoured at higher temperatures which enable Microcystis species to outcompete diatoms and green algae , and potentially allow development of toxins. Based on environmental trends, models and observations suggest cyanobacteria will likely increase their dominance in aquatic environments. This can lead to serious consequences, particularly
4116-487: Is known regarding the nature (e.g., genetic diversity, host or cyanobiont specificity, and cyanobiont seasonality) of the symbiosis involved, particularly in relation to dinoflagellate host. Some cyanobacteria – even single-celled ones – show striking collective behaviours and form colonies (or blooms ) that can float on water and have important ecological roles. For instance, billions of years ago, communities of marine Paleoproterozoic cyanobacteria could have helped create
4263-544: Is known. Zeaxanthin is also found in Prochlorococcus , red algae and as a minor pigment in some chlorophytes and eustigmatophytes . Similarly, phycoerythrin is also found in rhodophytes and some cryptomonads . Phylogenetic description of Synechococcus is difficult. Isolates are morphologically very similar, yet exhibit a G+C content ranging from 39 to 71%, illustrating the large genetic diversity of this provisional taxon. Initially, attempts were made to divide
4410-485: Is later used to make amino acids and proteins. Marine picocyanobacteria ( Prochlorococcus and Synechococcus ) numerically dominate most phytoplankton assemblages in modern oceans, contributing importantly to primary productivity. While some planktonic cyanobacteria are unicellular and free living cells (e.g., Crocosphaera , Prochlorococcus , Synechococcus ); others have established symbiotic relationships with haptophyte algae , such as coccolithophores . Amongst
4557-666: Is likely such a process gave Synechococcus photosynthesis. Marine Synechococcus species possess a set of genes that function in DNA recombination , repair and replication . This set of genes includes the recBCD gene complex whose product, exonuclease V, functions in recombinational repair of DNA, and the umuCD gene complex whose product, DNA polymerase V , functions in error-prone DNA replication. Some Synechococcus strains are naturally competent for genetic transformation , and thus can take up extracellular DNA and recombine it into their own genome. Synechococcus strains also encode
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4704-419: Is possibly the most plentiful genus on Earth: a single millilitre of surface seawater can contain 100,000 cells of this genus or more. Worldwide there are estimated to be several octillion (10 , a billion billion billion) individuals. Prochlorococcus is ubiquitous between latitudes 40°N and 40°S, and dominates in the oligotrophic (nutrient-poor) regions of the oceans. The bacterium accounts for about 20% of
4851-461: Is the second-largest U.S. state by area, after Alaska , and the largest state within the contiguous United States , at 268,820 square miles (696,200 km ). If it were an independent country, Texas would be the 39th-largest . It ranks 26th worldwide amongst country subdivisions by size . Texas is in the south central part of the United States. The Rio Grande forms a natural border with
4998-713: Is the most populous state in the South Central region of the United States . It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, and an international border with the Mexican states of Chihuahua , Coahuila , Nuevo León , and Tamaulipas to the south and southwest. Texas has a coastline on the Gulf of Mexico to the southeast. Covering 268,596 square miles (695,660 km ), and with over 30 million residents as of 2023, it
5145-515: Is the second-largest state by both area and population . Texas is nicknamed the Lone Star State for its former status as an independent republic . Spain was the first European country to claim and control Texas. Following a short-lived colony controlled by France, Mexico controlled the land until 1836 when Texas won its independence, becoming the Republic of Texas . In 1845, Texas joined
5292-523: Is thought to be at least 100 times more abundant than Synechococcus in warm oligotrophic waters. Assuming average cellular carbon concentrations, it has thus been estimated that Prochlorococcus accounts for at least 22 times more carbon in these waters, thus may be of much greater significance to the global carbon cycle than Synechococcus . Free floating viruses have been found carrying photosynthetic genes, and Synechococcus samples have been found to have viral proteins associated with photosynthesis. It
5439-509: Is unetymological, contrary to the historical value of the letter x ( / ʃ / ) in Spanish orthography . Alternative etymologies of the name advanced in the late 19th century connected the name Texas with the Spanish word teja , meaning 'roof tile', the plural tejas being used to designate Indigenous Pueblo settlements. A 1760s map by Jacques-Nicolas Bellin shows a village named Teijas on
5586-632: The Aranama , lived in southern Texas. This entire culture group, primarily centered in northeastern Mexico , is now extinct. No culture was dominant across all of present-day Texas, and many peoples inhabited the area. Native American tribes who have lived inside the boundaries of present-day Texas include the Alabama , Apache , Atakapan , Bidai , Caddo , Aranama , Comanche , Choctaw , Coushatta , Hasinai , Jumano , Karankawa , Kickapoo , Kiowa , Tonkawa , and Wichita . Many of these peoples migrated from
5733-577: The Battle of Gonzales . This launched the Texas Revolution . Texians elected delegates to the Consultation , which created a provisional government. The provisional government soon collapsed from infighting, and Texas was without clear governance for the first two months of 1836. Mexican President Antonio López de Santa Anna personally led an army to end the revolt. General José de Urrea defeated all
5880-637: The Democratic Party as the dominant party in the state. Beginning in the early 21st century, metropolitan areas including Dallas–Fort Worth and Greater Austin became centers for the Texas Democratic Party in statewide and national elections as liberal policies became more accepted in urban areas. From the mid-2000s to 2019, Texas gained an influx of business relocations and regional headquarters from companies in California . Texas became
6027-508: The Gulf of Mexico . The resulting " oil boom " transformed Texas. Oil production averaged three million barrels per day at its peak in 1972. In 1901, the Democratic-dominated state legislature passed a bill requiring payment of a poll tax for voting, which effectively disenfranchised most Black and many poor White and Latino people. In addition, the legislature established white primaries , ensuring minorities were excluded from
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6174-670: The McMurdo Sound and Ross Ice Shelf in Antarctica . Cells are generally much more abundant in nutrient-rich environments than in the oligotrophic ocean and prefer the upper, well-lit portion of the euphotic zone. Synechococcus has also been observed to occur at high abundances in environments with low salinities and/or low temperatures. It is usually far outnumbered by Prochlorococcus in all environments where they co-occur. Exceptions to this rule are areas of permanently enriched nutrients such as upwelling areas and coastal watersheds . In
6321-715: The Mississippian culture , also known as Mound Builders , which extended along the Mississippi River Valley east of Texas; and the civilizations of Mesoamerica , which were centered south of Texas. Influence of Teotihuacan in northern Mexico peaked around AD 500 and declined between the 8th and 10th centuries. When Europeans arrived in the Texas region, the language families present in the state were Caddoan, Atakapan , Athabaskan, Coahuiltecan , and Uto-Aztecan, in addition to several language isolates such as Tonkawa . Uto-Aztecan Puebloan and Jumano peoples lived neared
6468-611: The Old Three Hundred , made places along the Brazos River in 1822. The population of Texas grew rapidly. In 1825, Texas had about 3,500 people, with most of Mexican descent. By 1834, the population had grown to about 37,800 people, with only 7,800 of Mexican descent. Many immigrants openly flouted Mexican law, especially the prohibition against slavery . Combined with United States' attempts to purchase Texas, Mexican authorities decided in 1830 to prohibit continued immigration from
6615-553: The Pacific Ocean . Their opponents, led by Sam Houston, advocated the annexation of Texas to the United States and peaceful co-existence with Native Americans. The conflict between the factions was typified by an incident known as the Texas Archive War . With wide popular support, Texas first applied for annexation to the United States in 1836, but its status as a slaveholding country caused its admission to be controversial and it
6762-534: The Saint Malo settlement assisting Jean Lafitte in the Battle of New Orleans . In 1821, the Mexican War of Independence included the Texas territory, which became part of Mexico. Due to its low population, the territory was assigned to other states and territories of Mexico ; the core territory was part of the state of Coahuila y Tejas , but other parts of today's Texas were part of Tamaulipas , Chihuahua , or
6909-665: The Trinity River , close to the site of modern Crockett . Texas lies between two major cultural spheres of Pre-Columbian North America : the Southwestern and the Plains areas. Archaeologists have found that three major Indigenous cultures lived in this territory, and reached their developmental peak before the first European contact. These were: the Ancestral Puebloans from the upper Rio Grande region, centered west of Texas;
7056-449: The biosphere as we know it by burying carbon compounds and allowing the initial build-up of oxygen in the atmosphere. On the other hand, toxic cyanobacterial blooms are an increasing issue for society, as their toxins can be harmful to animals. Extreme blooms can also deplete water of oxygen and reduce the penetration of sunlight and visibility, thereby compromising the feeding and mating behaviour of light-reliant species. As shown in
7203-486: The black band disease ). Cyanobacteria can be found in almost every terrestrial and aquatic habitat – oceans , fresh water , damp soil, temporarily moistened rocks in deserts , bare rock and soil, and even Antarctic rocks. They can occur as planktonic cells or form phototrophic biofilms . They are found inside stones and shells (in endolithic ecosystems ). A few are endosymbionts in lichens , plants, various protists , or sponges and provide energy for
7350-518: The central gyres , where cell abundances are often very low, population growth rates are often high and not drastically limited. Factors such as grazing, viral mortality, genetic variability, light adaptation, and temperature, as well as nutrients are certainly involved, but remain to be investigated on a rigorous and global scale. Despite the uncertainties, a relationship probably exists between ambient nitrogen concentrations and Synechococcus abundance, with an inverse relationship to Prochlorococcus in
7497-620: The early Earth 's anoxic, weakly reducing prebiotic atmosphere , into an oxidizing one with free gaseous oxygen (which previously would have been immediately removed by various surface reductants ), resulting in the Great Oxidation Event and the " rusting of the Earth " during the early Proterozoic , dramatically changing the composition of life forms on Earth. The subsequent adaptation of early single-celled organisms to survive in oxygenous environments likely had led to endosymbiosis between anaerobes and aerobes , and hence
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#17330845527617644-553: The election of 1860 . During this time, Black people comprised 30 percent of the state's population, and they were overwhelmingly enslaved. When Abraham Lincoln was elected, South Carolina seceded from the Union; five other Deep South states quickly followed. A state convention considering secession opened in Austin on January 28, 1861. On February 1, by a vote of 166–8, the convention adopted an Ordinance of Secession . Texas voters approved this Ordinance on February 23, 1861. Texas joined
7791-672: The federalists against the government and drove all Mexican soldiers out of East Texas. They took advantage of the lack of oversight to agitate for more political freedom. Texians met at the Convention of 1832 to discuss requesting independent statehood, among other issues. The following year, Texians reiterated their demands at the Convention of 1833 . Within Mexico, tensions continued between federalists and centralists. In early 1835, wary Texians formed Committees of Correspondence and Safety. The unrest erupted into armed conflict in late 1835 at
7938-448: The filamentous species , which often dominate the upper layers of microbial mats found in extreme environments such as hot springs , hypersaline water , deserts and the polar regions, but are also widely distributed in more mundane environments as well. They are evolutionarily optimized for environmental conditions of low oxygen. Some species are nitrogen-fixing and live in a wide variety of moist soils and water, either freely or in
8085-501: The host . Some live in the fur of sloths , providing a form of camouflage . Aquatic cyanobacteria are known for their extensive and highly visible blooms that can form in both freshwater and marine environments. The blooms can have the appearance of blue-green paint or scum. These blooms can be toxic , and frequently lead to the closure of recreational waters when spotted. Marine bacteriophages are significant parasites of unicellular marine cyanobacteria. Cyanobacterial growth
8232-470: The water column . In the Pacific high-nutrient, low-chlorophyll zone and in temperate open seas where stratification was recently established both profiles parallel each other and exhibit abundance maxima just about the subsurface chlorophyll maximum. The factors controlling the abundance of Synechococcus still remain poorly understood, especially considering that even in the most nutrient-depleted regions of
8379-671: The Caddo meant that few were converted. Positioned between French Louisiana and Spanish Texas, the Caddo maintained relations with both, but were closer with the French. After Spain took control of Louisiana, most of the missions in eastern Texas were closed and abandoned. The United States obtained Louisiana following the 1803 Louisiana Purchase and began convincing tribes to self-segregate from whites by moving west; facing an overflow of native peoples in Missouri and Arkansas, they were able to negotiate with
8526-564: The Caddo of Louisiana and Arkansas. Following the Texas Revolution, the Texans chose to make peace with the Indigenous people, but did not honor former land claims or agreements. The first president of Texas, Sam Houston , aimed to cooperate and make peace with Native tribes, but his successor, Mirabeau B. Lamar , took a much more hostile stance. Hostility towards Natives by white Texans prompted
8673-558: The Caddo to allow several displaced peoples to settle on unused lands in eastern Texas. These included the Muscogee , Houma Choctaw , Lenape and Mingo Seneca , among others, who came to view the Caddoans as saviors. The temperament of Native American tribes affected the fates of European explorers and settlers in that land. Friendly tribes taught newcomers how to grow local crops, prepare foods, and hunt wild game . Warlike tribes resisted
8820-520: The Caddo, with the U.S. government trying to keep them in check. The Caddo never turned to violence because of the situation, except in cases of self-defense. By the 1830s, the U.S. had drafted the Indian Removal Act, which was used to facilitate the Trail of Tears. Fearing retribution, Indian Agents all over the eastern U.S. tried to convince all Indigenous peoples to uproot and move west. This included
8967-466: The Caddo. After Caddo resistance, the Spanish missionaries returned to Mexico. When France began settling Louisiana , in 1716 Spanish authorities responded by founding a new series of missions in East Texas. Two years later, they created San Antonio as the first Spanish civilian settlement in the area. Hostile native tribes and distance from nearby Spanish colonies discouraged settlers from moving to
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#17330845527619114-458: The Civil War and the restoration of its representation in the federal government, Texas entered a long period of economic stagnation. Historically, five major industries shaped the Texas economy prior to World War II : cattle, bison, cotton, timber, and oil. Before and after the Civil War, the cattle industry—which Texas came to dominate—was a major economic driver and created the traditional image of
9261-585: The Confederacy, Houston was deposed. While far from the major battlefields of the American Civil War , Texas contributed large numbers of soldiers and equipment. Union troops briefly occupied the state's primary port, Galveston. Texas's border with Mexico was known as the "backdoor of the Confederacy" because trade occurred at the border, bypassing the Union blockade. The Confederacy repulsed all Union attempts to shut down this route, but Texas's role as
9408-641: The Convention disbanded. The new government joined the other settlers in Texas in the Runaway Scrape , fleeing from the approaching Mexican army. After several weeks of retreat, the Texian Army commanded by Sam Houston attacked and defeated López de Santa Anna's forces at the Battle of San Jacinto . López de Santa Anna was captured and forced to sign the Treaties of Velasco , ending the war. The Constitution of
9555-464: The Earth's ecosystems. Planktonic cyanobacteria are a fundamental component of marine food webs and are major contributors to global carbon and nitrogen fluxes . Some cyanobacteria form harmful algal blooms causing the disruption of aquatic ecosystem services and intoxication of wildlife and humans by the production of powerful toxins ( cyanotoxins ) such as microcystins , saxitoxin , and cylindrospermopsin . Nowadays, cyanobacterial blooms pose
9702-514: The Mexican Territory of Santa Fe de Nuevo México . Hoping more settlers would reduce the near-constant Comanche raids, Mexican Texas liberalized its immigration policies to permit immigrants from outside Mexico and Spain. Large swathes of land were allotted to empresarios , who recruited settlers from the United States, Europe, and the Mexican interior, primarily the U.S. Austin's settlers,
9849-426: The Mexican states of Chihuahua , Coahuila , Nuevo León , and Tamaulipas to the south. The Red River forms a natural border with Oklahoma and Arkansas to the north. The Sabine River forms a natural border with Louisiana to the east. The Texas Panhandle has an eastern border with Oklahoma at 100° W , a northern border with Oklahoma at 36°30' N and a western border with New Mexico at 103° W . El Paso lies on
9996-476: The Northern United States or California and to escape segregation. In 1940, Texas was 74% White , 14.4% Black, and 11.5% Hispanic. World War II had a dramatic impact on Texas, as federal money poured in to build military bases, munitions factories, detention camps and Army hospitals; 750,000 Texans left for service; the cities exploded with new industry; and hundreds of thousands of poor farmers left
10143-601: The Philippines'), or as provincia de los Tejas ('province of the Tejas '), later also provincia de Texas (or de Tejas ), ('province of Texas'). It was incorporated as provincia de Texas into the Mexican Empire in 1821, and declared a republic in 1836. The Royal Spanish Academy recognizes both spellings, Tejas and Texas , as Spanish-language forms of the name. The English pronunciation with /ks/
10290-514: The Republic of Texas prohibited the government from restricting slavery or freeing slaves, and required free people of African descent to leave the country. Political battles raged between two factions of the new Republic. The nationalist faction, led by Mirabeau B. Lamar , advocated the continued independence of Texas, the expulsion of the Native Americans , and the expansion of the Republic to
10437-719: The Rio Grande in the western portion of the state and the Athabaskan-speaking Apache tribes lived throughout the interior. The agricultural, mound-building Caddo controlled much of the northeastern part of the state, along the Red , Sabine , and Neches River basins. Atakapan peoples such as the Akokisa and Bidai lived along the northeastern Gulf Coast; the Karankawa lived along the central coast. At least one tribe of Coahuiltecans ,
10584-620: The Rio Grande on January 13, 1846. A few months later Mexican troops routed an American cavalry patrol in the disputed area in the Thornton Affair starting the Mexican–American War . The first battles of the war were fought in Texas: the Siege of Fort Texas , Battle of Palo Alto and Battle of Resaca de la Palma . After these decisive victories, the United States invaded Mexican territory, ending
10731-399: The Texas cowboy. In the later 19th century, cotton and lumber grew to be major industries as the cattle industry became less lucrative. Ultimately, the discovery of major petroleum deposits ( Spindletop in particular) initiated an economic boom that became the driving force behind the economy for much of the 20th century. Texas developed a diversified economy and high tech industry during
10878-587: The Texian resistance along the coast culminating in the Goliad massacre . López de Santa Anna's forces, after a thirteen-day siege , overwhelmed Texian defenders at the Battle of the Alamo . News of the defeats sparked panic among Texas settlers. The newly elected Texian delegates to the Convention of 1836 quickly signed a declaration of independence on March 2, forming the Republic of Texas . After electing interim officers,
11025-597: The U.S. After Texas's annexation, Mexico broke diplomatic relations with the United States. While the United States claimed Texas's border stretched to the Rio Grande, Mexico claimed it was the Nueces River leaving the Rio Grande Valley under contested Texan sovereignty. While the former Republic of Texas could not enforce its border claims, the United States had the military strength and the political will to do so. President Polk ordered General Zachary Taylor south to
11172-459: The United States of America as the 28th state. The state's annexation set off a chain of events that led to the Mexican–American War in 1846. Following victory by the United States, Texas remained a slave state until the American Civil War , when it declared its secession from the Union in early 1861 before officially joining the Confederate States of America on March 2. After
11319-444: The United States. However, illegal immigration from the United States into Mexico continued to increase the population of Texas. New laws also called for the enforcement of customs duties angering native Mexican citizens ( Tejanos ) and recent immigrants alike. The Anahuac Disturbances in 1832 were the first open revolt against Mexican rule, coinciding with a revolt in Mexico against the nation's president. Texians sided with
11466-602: The accumulation of particulate organic carbon (cells, sheaths and heterotrophic organisms) in clumps. It has been unclear why and how cyanobacteria form communities. Aggregation must divert resources away from the core business of making more cyanobacteria, as it generally involves the production of copious quantities of extracellular material. In addition, cells in the centre of dense aggregates can also suffer from both shading and shortage of nutrients. So, what advantage does this communal life bring for cyanobacteria? New insights into how cyanobacteria form blooms have come from
11613-490: The activities of ancient cyanobacteria. They are often found as symbionts with a number of other groups of organisms such as fungi (lichens), corals , pteridophytes ( Azolla ), angiosperms ( Gunnera ), etc. The carbon metabolism of cyanobacteria include the incomplete Krebs cycle , the pentose phosphate pathway , and glycolysis . There are some groups capable of heterotrophic growth, while others are parasitic , causing diseases in invertebrates or algae (e.g.,
11760-514: The agreement. Several filibusters raised armies to invade the area west of the Sabine River. Marked by the War of 1812 , some men who had escaped from the Spanish, held (Old) Philippines had immigrated to and also passed through Texas (New Philippines) and reached Louisiana where Philippine exiles aided the United States in the defense of New Orleans against a British invasion, with Filipinos in
11907-480: The appropriate environmental conditions (anoxic) when fixed nitrogen is scarce. Heterocyst-forming species are specialized for nitrogen fixation and are able to fix nitrogen gas into ammonia ( NH 3 ), nitrites ( NO − 2 ) or nitrates ( NO − 3 ), which can be absorbed by plants and converted to protein and nucleic acids (atmospheric nitrogen is not bioavailable to plants, except for those having endosymbiotic nitrogen-fixing bacteria , especially
12054-561: The area. It was one of New Spain's least populated provinces. In 1749, the Spanish peace treaty with the Lipan Apache angered many tribes, including the Comanche, Tonkawa, and Hasinai. The Comanche signed a treaty with Spain in 1785 and later helped to defeat the Lipan Apache and Karankawa tribes. With numerous missions being established, priests led a peaceful conversion of most tribes. By
12201-448: The basis of cyanobacteria's informal common name , blue-green algae , although as prokaryotes they are not scientifically classified as algae . Cyanobacteria are probably the most numerous taxon to have ever existed on Earth and the first organisms known to have produced oxygen , having appeared in the middle Archean eon and apparently originated in a freshwater or terrestrial environment . Their photopigments can absorb
12348-432: The clump from the overlying medium and is also produced within the clump by respiration. In oxic solutions, high O 2 concentrations reduce the efficiency of CO 2 fixation and result in the excretion of glycolate. Under these conditions, clumping can be beneficial to cyanobacteria if it stimulates the retention of carbon and the assimilation of inorganic carbon by cyanobacteria within clumps. This effect appears to promote
12495-434: The coastal and the open ocean. All strains are obligate photoautrophs and are around 0.6–1.7 μm in diameter. This cluster is, however, further divided into a population that either contains (cluster 5.1) or does not contain (cluster 5.2) phycoerythrin. The reference strains are WH8103 for the phycoerythrin-containing strains and WH5701 for those strains that lack this pigment. More recently, Badger et al. (2002) proposed
12642-508: The colony of Fort Saint Louis at Matagorda Bay rather than along the Mississippi River . The colony lasted only four years before succumbing to harsh conditions and hostile natives. A small band of survivors traveled eastward into the lands of the Caddo, but La Salle was killed by disgruntled expedition members. In 1690 Spanish authorities, concerned that France posed a competitive threat, constructed several missions in East Texas among
12789-419: The common ancestor. Moreover, it has been estimated based on molecular dating that the first Synechococcus lineage has appeared 3 billion years ago in thermal springs with subsequent radiation to marine and freshwater environments. Synechococcus has been observed to occur at concentrations ranging between a few cells to 10 cells per ml in virtually all regions of oceanic euphotic zone except in samples from
12936-918: The contamination of sources of drinking water . Researchers including Linda Lawton at Robert Gordon University , have developed techniques to study these. Cyanobacteria can interfere with water treatment in various ways, primarily by plugging filters (often large beds of sand and similar media) and by producing cyanotoxins , which have the potential to cause serious illness if consumed. Consequences may also lie within fisheries and waste management practices. Anthropogenic eutrophication , rising temperatures, vertical stratification and increased atmospheric carbon dioxide are contributors to cyanobacteria increasing dominance of aquatic ecosystems. Cyanobacteria have been found to play an important role in terrestrial habitats and organism communities. It has been widely reported that cyanobacteria soil crusts help to stabilize soil to prevent erosion and retain water. An example of
13083-434: The cyanobacteria, only a few lineages colonized the open ocean: Crocosphaera and relatives, cyanobacterium UCYN-A , Trichodesmium , as well as Prochlorococcus and Synechococcus . From these lineages, nitrogen-fixing cyanobacteria are particularly important because they exert a control on primary productivity and the export of organic carbon to the deep ocean, by converting nitrogen gas into ammonium, which
13230-505: The cyanobacterial group. In general, photosynthesis in cyanobacteria uses water as an electron donor and produces oxygen as a byproduct, though some may also use hydrogen sulfide a process which occurs among other photosynthetic bacteria such as the purple sulfur bacteria . Carbon dioxide is reduced to form carbohydrates via the Calvin cycle . The large amounts of oxygen in the atmosphere are considered to have been first created by
13377-462: The cyanobacterium form buoyant aggregates by trapping oxygen bubbles in the slimy web of cells and polysaccharides. Previous studies on Synechocystis have shown type IV pili , which decorate the surface of cyanobacteria, also play a role in forming blooms. These retractable and adhesive protein fibres are important for motility, adhesion to substrates and DNA uptake. The formation of blooms may require both type IV pili and Synechan – for example,
13524-494: The cytoplasm of the cell. Carboxysomes are icosahedral structures composed of hexameric shell proteins that assemble into cage-like structures that can be several hundreds of nanometres in diameter. It is believed that these structures tether the CO 2 -fixing enzyme, RuBisCO , to the interior of the shell, as well as the enzyme carbonic anhydrase , using metabolic channeling to enhance the local CO 2 concentrations and thus increase
13671-600: The desert and mountains of the Big Bend . The name Texas , based on the Caddo word táy:shaʼ ( /tə́jːʃaʔ/ ) 'friend', was applied, in the spelling Tejas or Texas , by the Spanish to the Caddo themselves, specifically the Hasinai Confederacy. During Spanish colonial rule , in the 18th century, the area was known as Nuevas Filipinas (' New Philippines ') and Nuevo Reino de Filipinas ('New Kingdom of
13818-432: The diagram on the right, bacteria can stay in suspension as individual cells, adhere collectively to surfaces to form biofilms, passively sediment, or flocculate to form suspended aggregates. Cyanobacteria are able to produce sulphated polysaccharides (yellow haze surrounding clumps of cells) that enable them to form floating aggregates. In 2021, Maeda et al. discovered that oxygen produced by cyanobacteria becomes trapped in
13965-769: The division of the cyanobacteria into a α- and a β-subcluster based on the type of rbcL (large subunit of ribulose 1,5-bisphosphate carboxylase/oxygenase ) found in these organisms. α-cyanobacteria were defined to contain a form IA, while β-cyanobacteria were defined to contain a form IB of this gene. In support for this division Badger et al. analyze the phylogeny of carboxysomal proteins, which appear to support this division. Also, two particular bicarbonate transport systems appear to only be found in α-cyanobacteria, which lack carboxysomal carbonic anhydrases. The complete phylogenetic tree of 16S rRNA sequences of Synechococcus revealed at least 12 groups, which morphologically correspond to Synechococcus , but they have not derived from
14112-529: The early months of Reconstruction . Juneteenth commemorates the announcement of the Emancipation Proclamation in Galveston by General Gordon Granger, almost two and a half years after the original announcement. President Johnson, in 1866, declared the civilian government restored in Texas. Despite not meeting Reconstruction requirements, Congress resumed allowing elected Texas representatives into
14259-583: The east, seeking a route to Mexico. They passed through the Caddo lands but turned back after reaching the River of Daycao (possibly the Brazos or Colorado), beyond which point the Native peoples were nomadic and did not have the agricultural stores to feed the expedition. European powers ignored the area until accidentally settling there in 1685. Miscalculations by René-Robert Cavelier de La Salle resulted in his establishing
14406-474: The economy. Amid a rise in COVID-19 cases in autumn 2020, Abbott refused to enact further lockdowns. In November 2020, Texas was selected as one of four states to test Pfizer's COVID-19 vaccine distribution. As of February 2, 2021, there had been over 2.4 million confirmed cases in Texas, with at least 37,417 deaths. During February 13–17, 2021, the state faced a major weather emergency as Winter Storm Uri hit
14553-459: The efficiency of the RuBisCO enzyme. In contrast to purple bacteria and other bacteria performing anoxygenic photosynthesis , thylakoid membranes of cyanobacteria are not continuous with the plasma membrane but are separate compartments. The photosynthetic machinery is embedded in the thylakoid membranes, with phycobilisomes acting as light-harvesting antennae attached to the membrane, giving
14700-470: The end of the 18th century only a few nomadic tribes had not converted. When the United States purchased Louisiana from France in 1803, American authorities insisted the agreement also included Texas. The boundary between New Spain and the United States was finally set in 1819 at the Sabine River , the modern border between Texas and Louisiana. Eager for new land, many U.S. settlers refused to recognize
14847-922: The evolution of eukaryotes during the Paleoproterozoic . Cyanobacteria use photosynthetic pigments such as various forms of chlorophyll , carotenoids , phycobilins to convert the photonic energy in sunlight to chemical energy . Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes . These are flattened sacs called thylakoids where photosynthesis is performed. Photoautotrophic eukaryotes such as red algae , green algae and plants perform photosynthesis in chlorophyllic organelles that are thought to have their ancestry in cyanobacteria, acquired long ago via endosymbiosis. These endosymbiont cyanobacteria in eukaryotes then evolved and differentiated into specialized organelles such as chloroplasts , chromoplasts , etioplasts , and leucoplasts , collectively known as plastids . Sericytochromatia,
14994-443: The family Fabaceae , among others). Free-living cyanobacteria are present in the water of rice paddies , and cyanobacteria can be found growing as epiphytes on the surfaces of the green alga, Chara , where they may fix nitrogen. Cyanobacteria such as Anabaena (a symbiont of the aquatic fern Azolla ) can provide rice plantations with biofertilizer . Cyanobacteria use the energy of sunlight to drive photosynthesis ,
15141-612: The federal government for their opposition to U.S. involvement in World War I . The Great Depression and the Dust Bowl dealt a double blow to the state's economy, which had significantly improved since the Civil War. Migrants abandoned the worst-hit sections of Texas during the Dust Bowl years. Especially from this period on, Black people left Texas in the Great Migration to get work in
15288-498: The federal government in 1870. Social volatility continued as the state struggled with agricultural depression and labor issues. Like most of the South, the Texas economy was devastated by the War. However, since the state had not been as dependent on slaves as other parts of the South, it was able to recover more quickly. The culture in Texas during the later 19th century exhibited many facets of
15435-406: The fields for much better-paying war jobs, never to return to agriculture. Texas manufactured 3.1 percent of total United States military armaments produced during World War II, ranking eleventh among the 48 states. Texas modernized and expanded its system of higher education through the 1960s. The state created a comprehensive plan for higher education, funded in large part by oil revenues, and
15582-589: The fighting in Texas. The Treaty of Guadalupe Hidalgo ended the two-year war. In return for US$ 18,250,000, Mexico gave the U.S. undisputed control of Texas, ceded the Mexican Cession in 1848, most of which today is called the American Southwest, and Texas's borders were established at the Rio Grande. The Compromise of 1850 set Texas's boundaries at their present position: Texas ceded its claims to land which later became half of present-day New Mexico ,
15729-477: The filamentous forms, Trichodesmium are free-living and form aggregates. However, filamentous heterocyst-forming cyanobacteria (e.g., Richelia , Calothrix ) are found in association with diatoms such as Hemiaulus , Rhizosolenia and Chaetoceros . Marine cyanobacteria include the smallest known photosynthetic organisms. The smallest of all, Prochlorococcus , is just 0.5 to 0.8 micrometres across. In terms of numbers of individuals, Prochlorococcus
15876-493: The first Europeans in what is now Texas. Cabeza de Vaca reported that in 1528, when the Spanish landed in the area, "half the natives died from a disease of the bowels and blamed us." Cabeza de Vaca also made observations about the way of life of the Ignaces Natives of Texas. Francisco Vázquez de Coronado described another encounter with native people in 1541. The expedition of Hernando de Soto entered into Texas from
16023-408: The first signs of multicellularity. Many cyanobacteria form motile filaments of cells, called hormogonia , that travel away from the main biomass to bud and form new colonies elsewhere. The cells in a hormogonium are often thinner than in the vegetative state, and the cells on either end of the motile chain may be tapered. To break away from the parent colony, a hormogonium often must tear apart
16170-569: The formal political process. The number of voters dropped dramatically, and the Democrats crushed competition from the Republican and Populist parties. The Socialist Party became the second-largest party in Texas after 1912, coinciding with a large socialist upsurge in the United States during fierce battles in the labor movement and the popularity of national heroes like Eugene V. Debs . The socialists' popularity soon waned after their vilification by
16317-650: The gene lexA that regulates an SOS response system, that is likely similar to the well-studied E. coli SOS system that is employed in the response to DNA damage . Cyanobacterium As of 2014 the taxonomy was under revision Cyanobacteria ( / s aɪ ˌ æ n oʊ b æ k ˈ t ɪər i . ə / ), also called Cyanobacteriota or Cyanophyta , are a phylum of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis . The name "cyanobacteria" (from Ancient Greek κύανος ( kúanos ) 'blue') refers to their bluish green ( cyan ) color, which forms
16464-481: The green pigmentation observed (with wavelengths from 450 nm to 660 nm) in most cyanobacteria. While most of the high-energy electrons derived from water are used by the cyanobacterial cells for their own needs, a fraction of these electrons may be donated to the external environment via electrogenic activity. Respiration in cyanobacteria can occur in the thylakoid membrane alongside photosynthesis, with their photosynthetic electron transport sharing
16611-726: The group into three subclusters, each with a specific range of genomic G+C content. The observation that open-ocean isolates alone nearly span the complete G+C spectrum, however, indicates that Synechococcus is composed of at least several species. Bergey's Manual (Herdman et al. 2001) now divides Synechococcus into five clusters (equivalent to genera) based on morphology, physiology, and genetic traits. Cluster 1 includes relatively large (1–1.5 μm) nonmotile obligate photoautotrophs that exhibit low salt tolerance. Reference strains for this cluster are PCC6301 (formerly Anacycstis nidulans ) and PCC6312, which were isolated from fresh water in Texas and California , respectively. Cluster 2 also
16758-417: The head and tail vary among species of cyanophages. Cyanophages, like other bacteriophages , rely on Brownian motion to collide with bacteria, and then use receptor binding proteins to recognize cell surface proteins, which leads to adherence. Viruses with contractile tails then rely on receptors found on their tails to recognize highly conserved proteins on the surface of the host cell. Cyanophages infect
16905-500: The mid-20th century. As of 2022 , it has the most Fortune 500 company headquarters (53) in the United States. With a growing base of industry, the state leads in many industries, including tourism , agriculture , petrochemicals , energy , computers and electronics , aerospace , and biomedical sciences . Texas has led the U.S. in state export revenue since 2002 and has the second-highest gross state product . The Dallas–Fort Worth metroplex and Greater Houston areas are
17052-544: The most abundant photosynthetic organisms on Earth, accounting for a quarter of all carbon fixed in marine ecosystems. In contrast to free-living marine cyanobacteria, some cyanobionts are known to be responsible for nitrogen fixation rather than carbon fixation in the host. However, the physiological functions of most cyanobionts remain unknown. Cyanobionts have been found in numerous protist groups, including dinoflagellates , tintinnids , radiolarians , amoebae , diatoms , and haptophytes . Among these cyanobionts, little
17199-453: The most extreme niches such as hot springs, salt works, and hypersaline bays. Photoautotrophic , oxygen-producing cyanobacteria created the conditions in the planet's early atmosphere that directed the evolution of aerobic metabolism and eukaryotic photosynthesis. Cyanobacteria fulfill vital ecological functions in the world's oceans, being important contributors to global carbon and nitrogen budgets." – Stewart and Falconer Some cyanobacteria,
17346-683: The movement of most Native populations north into what would become Indian Territory (modern Oklahoma). Only the Alabama-Coushatta would remain in the parts of Texas subject to white settlement, though the Comanche would continue to control most of the western half of the state until their defeat in the 1870s and 1880s. The first historical document related to Texas was a map of the Gulf Coast , created in 1519 by Spanish explorer Alonso Álvarez de Pineda . Nine years later, shipwrecked Spanish explorer Álvar Núñez Cabeza de Vaca and his cohort became
17493-558: The nation's fourth and fifth-most populous urban regions respectively. Its capital city is Austin . Due to its size and geologic features such as the Balcones Fault , Texas contains diverse landscapes common to both the U.S. Southern and the Southwestern regions . Most population centers are in areas of former prairies , grasslands , forests, and the coastline . Traveling from east to west, terrain ranges from coastal swamps and piney woods , to rolling plains and rugged hills, to
17640-406: The network of polysaccharides and cells, enabling the microorganisms to form buoyant blooms. It is thought that specific protein fibres known as pili (represented as lines radiating from the cells) may act as an additional way to link cells to each other or onto surfaces. Some cyanobacteria also use sophisticated intracellular gas vesicles as floatation aids. The diagram on the left above shows
17787-537: The newly created Confederate States of America on March 4, 1861, ratifying the permanent C.S. Constitution on March 23. Not all Texans favored secession initially, although many of the same would later support the Southern cause. Texas's most notable Unionist was the state governor, Sam Houston . Not wanting to aggravate the situation, Houston refused two offers from President Lincoln for Union troops to keep him in office. After refusing to swear an oath of allegiance to
17934-562: The north or east during the colonial period, such as the Choctaw , Alabama-Coushatta, and Delaware . The region was primarily controlled by the Spanish until the Texas Revolution . They were most interested in relationships with the Caddo, who were—like the Spanish—a settled, agricultural people. Several Spanish missions were opened in Caddo territory, but a lack of interest in Christianity among
18081-610: The nutrient-depleted areas of the oceans, such as the central gyres, Synechococcus is apparently always present, although only at low concentrations, ranging from a few to 4×10³ cells per ml. Vertically Synechococcus is usually relatively equitably distributed throughout the mixed layer and exhibits an affinity for the higher-light areas. Below the mixed layer, cell concentrations rapidly decline. Vertical profiles are strongly influenced by hydrologic conditions and can be very variable both seasonally and spatially. Overall, Synechococcus abundance often parallels that of Prochlorococcus in
18228-418: The oxygen in the Earth's atmosphere. Cyanobacteria are variable in morphology, ranging from unicellular and filamentous to colonial forms . Filamentous forms exhibit functional cell differentiation such as heterocysts (for nitrogen fixation), akinetes (resting stage cells), and hormogonia (reproductive, motile filaments). These, together with the intercellular connections they possess, are considered
18375-716: The photosystems. The phycobilisome components ( phycobiliproteins ) are responsible for the blue-green pigmentation of most cyanobacteria. The variations on this theme are due mainly to carotenoids and phycoerythrins that give the cells their red-brownish coloration. In some cyanobacteria, the color of light influences the composition of the phycobilisomes. In green light, the cells accumulate more phycoerythrin, which absorbs green light, whereas in red light they produce more phycocyanin which absorbs red. Thus, these bacteria can change from brick-red to bright blue-green depending on whether they are exposed to green light or to red light. This process of "complementary chromatic adaptation"
18522-443: The pili may allow cyanobacteria from the same species to recognise each other and make initial contacts, which are then stabilised by building a mass of extracellular polysaccharide. The bubble flotation mechanism identified by Maeda et al. joins a range of known strategies that enable cyanobacteria to control their buoyancy, such as using gas vesicles or accumulating carbohydrate ballasts. Type IV pili on their own could also control
18669-413: The pili may help to export the polysaccharide outside the cell. Indeed, the activity of these protein fibres may be connected to the production of extracellular polysaccharides in filamentous cyanobacteria. A more obvious answer would be that pili help to build the aggregates by binding the cells with each other or with the extracellular polysaccharide. As with other kinds of bacteria, certain components of
18816-485: The port at Galveston as commerce expanded. The lumber industry quickly expanded and was Texas' largest industry prior to the 20th century. In 1900, Texas suffered the deadliest natural disaster in U.S. history during the Galveston hurricane . On January 10, 1901, the first major oil well in Texas, Spindletop , was found south of Beaumont . Other fields were later discovered nearby in East Texas , West Texas , and under
18963-481: The position of marine cyanobacteria in the water column by regulating viscous drag. Extracellular polysaccharide appears to be a multipurpose asset for cyanobacteria, from floatation device to food storage, defence mechanism and mobility aid. One of the most critical processes determining cyanobacterial eco-physiology is cellular death . Evidence supports the existence of controlled cellular demise in cyanobacteria, and various forms of cell death have been described as
19110-550: The presence of phosphate inclusions, glycogen granules, and more importantly, highly structured carboxysomes . Cells are known to be motile by a gliding method and a novel uncharacterized, nonphototactic swimming method that does not involve flagellar motion . While some cyanobacteria are capable of photoheterotrophic or even chemoheterotrophic growth, all marine Synechococcus strains appear to be obligate photoautotrophs that are capable of supporting their nitrogen requirements using nitrate, ammonia, or in some cases urea as
19257-478: The proposed name of the paraphyletic and most basal group, is the ancestor of both the non-photosynthetic group Melainabacteria and the photosynthetic cyanobacteria, also called Oxyphotobacteria. The cyanobacteria Synechocystis and Cyanothece are important model organisms with potential applications in biotechnology for bioethanol production, food colorings, as a source of human and animal food, dietary supplements and raw materials. Cyanobacteria produce
19404-468: The red- and blue-spectrum frequencies of sunlight (thus reflecting a greenish color) to split water molecules into hydrogen ions and oxygen. The hydrogen ions are used to react with carbon dioxide to produce complex organic compounds such as carbohydrates (a process known as carbon fixation ), and the oxygen is released as a byproduct . By continuously producing and releasing oxygen over billions of years, cyanobacteria are thought to have converted
19551-573: The reference strain PCC7003, are facultative heterotrophs and require vitamin B 12 for growth. Cluster 4 contains a single isolate, PCC7335. This strain is obligate marine. This strain contains phycoerthrin and was first isolated from the intertidal zone in Puerto Peñasco , Mexico . The last cluster contains what had previously been referred to as ‘marine A and B clusters’ of Synechococcus . These cells are truly marine and have been isolated from both
19698-427: The reversal frequencies of any filaments that begin to leave the clumps, thereby reducing the net migration away from the clump. This enables the persistence of the initial clumps over short timescales; (b) Spatial coupling between photosynthesis and respiration in clumps. Oxygen produced by cyanobacteria diffuses into the overlying medium or is used for aerobic respiration. Dissolved inorganic carbon (DIC) diffuses into
19845-448: The root surface within a restricted zone by Nostoc . The relationships between cyanobionts (cyanobacterial symbionts) and protistan hosts are particularly noteworthy, as some nitrogen-fixing cyanobacteria ( diazotrophs ) play an important role in primary production , especially in nitrogen-limited oligotrophic oceans. Cyanobacteria, mostly pico-sized Synechococcus and Prochlorococcus , are ubiquitously distributed and are
19992-514: The roots of wheat and cotton plants. Calothrix sp. has also been found on the root system of wheat. Monocots , such as wheat and rice, have been colonised by Nostoc spp., In 1991, Ganther and others isolated diverse heterocystous nitrogen-fixing cyanobacteria, including Nostoc , Anabaena and Cylindrospermum , from plant root and soil. Assessment of wheat seedling roots revealed two types of association patterns: loose colonization of root hair by Anabaena and tight colonization of
20139-415: The same compartment as the components of respiratory electron transport. While the goal of photosynthesis is to store energy by building carbohydrates from CO 2 , respiration is the reverse of this, with carbohydrates turned back into CO 2 accompanying energy release. Cyanobacteria appear to separate these two processes with their plasma membrane containing only components of the respiratory chain, while
20286-429: The settlers. Prior treaties with the Spanish forbade either side from militarizing its native population in any potential conflict between the two nations. Several outbreaks of violence between Native Americans and Texans started to spread in the prelude to the Texas Revolution. Texans accused tribes of stealing livestock. While no proof was found, those in charge of Texas at the time attempted to publicly blame and punish
20433-543: The shortest doubling time at “1.9 hours in a BG11 medium at 41°C under continuous 500 μmoles photons·m−2·s−1 white light with 3% CO2”. The main photosynthetic pigment in Synechococcus is chlorophyll a , while its major accessory pigments are phycobiliprotein . The four commonly recognized phycobilins are phycocyanin , allophycocyanin , allophycocyanin B and phycoerythrin . In addition Synechococcus also contains zeaxanthin but no diagnostic pigment for this organism
20580-429: The so-called cyanobionts (cyanobacterial symbionts), have a symbiotic relationship with other organisms, both unicellular and multicellular. As illustrated on the right, there are many examples of cyanobacteria interacting symbiotically with land plants . Cyanobacteria can enter the plant through the stomata and colonize the intercellular space, forming loops and intracellular coils. Anabaena spp. colonize
20727-568: The state, as well as most of the Southeastern and Midwestern United States. Historically high power usage across the state caused the state's power grid to become overworked and ERCOT (the main operator of the Texas Interconnection grid) declared an emergency and began to implement rolling blackouts across Texas, causing a power crisis . Over 3 million Texans were without power and over 4 million were under boil-water notices. Texas
20874-473: The thylakoid membrane hosts an interlinked respiratory and photosynthetic electron transport chain. Cyanobacteria use electrons from succinate dehydrogenase rather than from NADPH for respiration. Cyanobacteria only respire during the night (or in the dark) because the facilities used for electron transport are used in reverse for photosynthesis while in the light. Many cyanobacteria are able to reduce nitrogen and carbon dioxide under aerobic conditions,
21021-456: The upper euphotic zone , where light is not limiting. One environment where Synechococcus thrives particularly well is coastal plumes of major rivers. Such plumes are coastally enriched with nutrients such as nitrate and phosphate, which drives large phytoplankton blooms . High productivity in coastal river plumes is often associated with large populations of Synechococcus and elevated form IA (cyanobacterial) rbcL mRNA. Prochlorococcus
21168-456: Was captured twice and Texans were defeated in battle in the Dawson massacre . Despite these successes, Mexico did not keep an occupying force in Texas, and the republic survived. The cotton price crash of the 1840s depressed the country's economy. Texas was finally annexed when the expansionist James K. Polk won the election of 1844 . On December 29, 1845, the U.S. Congress admitted Texas to
21315-411: Was discovered in 1963. Cyanophages are classified within the bacteriophage families Myoviridae (e.g. AS-1 , N-1 ), Podoviridae (e.g. LPP-1) and Siphoviridae (e.g. S-1 ). Texas Texas ( / ˈ t ɛ k s ə s / TEK -səss , locally also / ˈ t ɛ k s ɪ z / TEK -siz ; Spanish : Texas or Tejas , pronounced [ˈtexas] )
21462-500: Was discovered in 1986 and accounts for more than half of the photosynthesis of the open ocean. Circadian rhythms were once thought to only exist in eukaryotic cells but many cyanobacteria display a bacterial circadian rhythm . "Cyanobacteria are arguably the most successful group of microorganisms on earth. They are the most genetically diverse; they occupy a broad range of habitats across all latitudes, widespread in freshwater, marine, and terrestrial ecosystems, and they are found in
21609-525: Was initially rebuffed. This status, and Mexican diplomacy in support of its claims to the territory, also complicated Texas's ability to form foreign alliances and trade relationships. The Comanche Indians furnished the main Native American opposition to the Texas Republic, manifested in multiple raids on settlements . Mexico launched two small expeditions into Texas in 1842. The town of San Antonio
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