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58-405: Macromolecule Large molecule A molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. 1. In many cases, especially for synthetic polymers, a molecule can be regarded as having a high relative molecular mass if the addition or removal of one or

116-457: A few of the units has a negligible effect on the molecular properties. This statement fails in the case of certain macromolecules for which the properties may be critically dependent on fine details of the molecular structure. 2. If a part or the whole of the molecule fits into this definition, it may be described as either macromolecular or polymeric , or by polymer used adjectivally. The term macromolecule ( macro- + molecule )

174-465: A (d5SICS–dNaM) complex or base pair in DNA. E. coli have been induced to replicate a plasmid containing UBPs through multiple generations. This is the first known example of a living organism passing along an expanded genetic code to subsequent generations. The applications of synthetic nucleotides vary widely and include disease diagnosis, treatment, or precision medicine. Nucleotide (abbreviated "nt")

232-514: A Greek prefix meaning long or large) List of commonly used taxonomic affixes Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Macro . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Macro&oldid=1254189143 " Category : Disambiguation pages Hidden categories: Short description

290-516: A branched structure of multiple phenolic subunits. They can perform structural roles (e.g. lignin ) as well as roles as secondary metabolites involved in signalling , pigmentation and defense . Some examples of macromolecules are synthetic polymers ( plastics , synthetic fibers , and synthetic rubber ), graphene , and carbon nanotubes . Polymers may be prepared from inorganic matter as well as for instance in inorganic polymers and geopolymers . The incorporation of inorganic elements enables

348-413: A central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates , adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP), and uridine triphosphate (UTP)—throughout the cell for the many cellular functions that demand energy, including: amino acid , protein and cell membrane synthesis, moving

406-506: A diet and lifestyle based on eating natural, organic food Museum of Contemporary Art of Rome (MACRO), Italy Cox Macro (1686–1767), English Anglican priest and antiquarian Naevius Sutorius Macro (21 BC – 38 AD), praetorian prefect in the Roman Empire See also [ edit ] Marco (disambiguation) Makro , a retail brand Micro (disambiguation) Mikro (disambiguation) Large (disambiguation) ( macro :

464-466: A double helix, the two strands are oriented in opposite directions, which permits base pairing and complementarity between the base-pairs, all which is essential for replicating or transcribing the encoded information found in DNA. Nucleic acids then are polymeric macromolecules assembled from nucleotides, the monomer-units of nucleic acids . The purine bases adenine and guanine and pyrimidine base cytosine occur in both DNA and RNA, while

522-467: A large part of the volume of the solution, thereby increasing the effective concentrations of these molecules. All living organisms are dependent on three essential biopolymers for their biological functions: DNA , RNA and proteins . Each of these molecules is required for life since each plays a distinct, indispensable role in the cell . The simple summary is that DNA makes RNA, and then RNA makes proteins . DNA, RNA, and proteins all consist of

580-461: A much greater stability against breakdown than does RNA, an attribute primarily associated with the absence of the 2'-hydroxyl group within every nucleotide of DNA. Third, highly sophisticated DNA surveillance and repair systems are present which monitor damage to the DNA and repair the sequence when necessary. Analogous systems have not evolved for repairing damaged RNA molecules. Consequently, chromosomes can contain many billions of atoms, arranged in

638-483: A phosphorylated ribosyl unit. The covalent linkage between the ribose and pyrimidine occurs at position C 1 of the ribose unit, which contains a pyrophosphate , and N 1 of the pyrimidine ring. Orotate phosphoribosyltransferase (PRPP transferase) catalyzes the net reaction yielding orotidine monophosphate (OMP): Orotidine 5'-monophosphate is decarboxylated by orotidine-5'-phosphate decarboxylase to form uridine monophosphate (UMP). PRPP transferase catalyzes both

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696-402: A repeating structure of related building blocks ( nucleotides in the case of DNA and RNA, amino acids in the case of proteins). In general, they are all unbranched polymers, and so can be represented in the form of a string. Indeed, they can be viewed as a string of beads, with each bead representing a single nucleotide or amino acid monomer linked together through covalent chemical bonds into

754-399: A second one-carbon unit from formyl-THF is added to the nitrogen group and the ring is covalently closed to form the common purine precursor inosine monophosphate (IMP). Inosine monophosphate is converted to adenosine monophosphate in two steps. First, GTP hydrolysis fuels the addition of aspartate to IMP by adenylosuccinate synthase, substituting the carbonyl oxygen for a nitrogen and forming

812-438: A sequence of instructions or other outputs Macro key , a key found on some keyboards, particularly older keyboards. Media and entertainment [ edit ] Macromanagement (gameplay) , high-level decision making in games Macro Recordings , a German electronic music label Macro analysis of chords and chord progressions Macro , a 2019 album by Jinjer Other uses [ edit ] Macrobiotics ,

870-424: A specific chemical structure. Proteins are functional macromolecules responsible for catalysing the biochemical reactions that sustain life. Proteins carry out all functions of an organism, for example photosynthesis, neural function, vision, and movement. The single-stranded nature of protein molecules, together with their composition of 20 or more different amino acid building blocks, allows them to fold in to

928-409: A specified protein. On the other hand, the sequence information of a protein molecule is not used by cells to functionally encode genetic information. DNA has three primary attributes that allow it to be far better than RNA at encoding genetic information. First, it is normally double-stranded, so that there are a minimum of two copies of the information encoding each gene in every cell. Second, DNA has

986-459: A vast number of different three-dimensional shapes, while providing binding pockets through which they can specifically interact with all manner of molecules. In addition, the chemical diversity of the different amino acids, together with different chemical environments afforded by local 3D structure, enables many proteins to act as enzymes , catalyzing a wide range of specific biochemical transformations within cells. In addition, proteins have evolved

1044-1129: A very large number of three-dimensional structures. Some of these structures provide binding sites for other molecules and chemically active centers that can catalyze specific chemical reactions on those bound molecules. The limited number of different building blocks of RNA (4 nucleotides vs >20 amino acids in proteins), together with their lack of chemical diversity, results in catalytic RNA ( ribozymes ) being generally less-effective catalysts than proteins for most biological reactions. The Major Macromolecules: (Polymer) (Monomer) Carbohydrate macromolecules ( polysaccharides ) are formed from polymers of monosaccharides . Because monosaccharides have multiple functional groups , polysaccharides can form linear polymers (e.g. cellulose ) or complex branched structures (e.g. glycogen ). Polysaccharides perform numerous roles in living organisms, acting as energy stores (e.g. starch ) and as structural components (e.g. chitin in arthropods and fungi). Many carbohydrates contain modified monosaccharide units that have had functional groups replaced or removed. Polyphenols consist of

1102-442: A very long chain. In most cases, the monomers within the chain have a strong propensity to interact with other amino acids or nucleotides. In DNA and RNA, this can take the form of Watson–Crick base pairs (G–C and A–T or A–U), although many more complicated interactions can and do occur. Because of the double-stranded nature of DNA, essentially all of the nucleotides take the form of Watson–Crick base pairs between nucleotides on

1160-432: Is a common unit of length for single-stranded nucleic acids, similar to how base pair is a unit of length for double-stranded nucleic acids. The IUPAC has designated the symbols for nucleotides. Apart from the five (A, G, C, T/U) bases, often degenerate bases are used especially for designing PCR primers . These nucleotide codes are listed here. Some primer sequences may also include the character "I", which codes for

1218-464: Is different from Wikidata All article disambiguation pages All disambiguation pages Nucleotide Nucleotides are organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate . They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth . Nucleotides are obtained in

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1276-411: Is fueled by ATP hydrolysis. In humans, pyrimidine rings (C, T, U) can be degraded completely to CO 2 and NH 3 (urea excretion). That having been said, purine rings (G, A) cannot. Instead, they are degraded to the metabolically inert uric acid which is then excreted from the body. Uric acid is formed when GMP is split into the base guanine and ribose. Guanine is deaminated to xanthine which in turn

1334-432: Is oxidized to uric acid. This last reaction is irreversible. Similarly, uric acid can be formed when AMP is deaminated to IMP from which the ribose unit is removed to form hypoxanthine. Hypoxanthine is oxidized to xanthine and finally to uric acid. Instead of uric acid secretion, guanine and IMP can be used for recycling purposes and nucleic acid synthesis in the presence of PRPP and aspartate (NH 3 donor). Theories about

1392-543: Is protected to create a phosphoramidite , which can then be used to obtain analogues not found in nature and/or to synthesize an oligonucleotide . In vivo, nucleotides can be synthesized de novo or recycled through salvage pathways . The components used in de novo nucleotide synthesis are derived from biosynthetic precursors of carbohydrate and amino acid metabolism, and from ammonia and carbon dioxide. Recently it has been also demonstrated that cellular bicarbonate metabolism can be regulated by mTORC1 signaling. The liver

1450-527: Is subsequently formed by the amination of UTP by the catalytic activity of CTP synthetase . Glutamine is the NH 3 donor and the reaction is fueled by ATP hydrolysis, too: Cytidine monophosphate (CMP) is derived from cytidine triphosphate (CTP) with subsequent loss of two phosphates. The atoms that are used to build the purine nucleotides come from a variety of sources: The de novo synthesis of purine nucleotides by which these precursors are incorporated into

1508-435: Is the committed step in purine synthesis. The reaction occurs with the inversion of configuration about ribose C 1 , thereby forming β - 5-phosphorybosylamine (5-PRA) and establishing the anomeric form of the future nucleotide. Next, a glycine is incorporated fueled by ATP hydrolysis, and the carboxyl group forms an amine bond to the NH 2 previously introduced. A one-carbon unit from folic acid coenzyme N 10 -formyl-THF

1566-421: Is the major organ of de novo synthesis of all four nucleotides. De novo synthesis of pyrimidines and purines follows two different pathways. Pyrimidines are synthesized first from aspartate and carbamoyl-phosphate in the cytoplasm to the common precursor ring structure orotic acid, onto which a phosphorylated ribosyl unit is covalently linked. Purines, however, are first synthesized from the sugar template onto which

1624-530: Is their relative insolubility in water and similar solvents , instead forming colloids . Many require salts or particular ions to dissolve in water. Similarly, many proteins will denature if the solute concentration of their solution is too high or too low. High concentrations of macromolecules in a solution can alter the rates and equilibrium constants of the reactions of other macromolecules, through an effect known as macromolecular crowding . This comes from macromolecules excluding other molecules from

1682-413: Is then added to the amino group of the substituted glycine followed by the closure of the imidazole ring. Next, a second NH 2 group is transferred from glutamine to the first carbon of the glycine unit. A carboxylation of the second carbon of the glycin unit is concomitantly added. This new carbon is modified by the addition of a third NH 2 unit, this time transferred from an aspartate residue. Finally,

1740-407: The origin of life require knowledge of chemical pathways that permit formation of life's key building blocks under plausible prebiotic conditions. The RNA world hypothesis holds that in the primordial soup there existed free-floating ribonucleotides , the fundamental molecules that combine in series to form RNA . Complex molecules like RNA must have arisen from small molecules whose reactivity

1798-406: The pyrimidine nucleotides . Being on a major metabolic crossroad and requiring much energy, this reaction is highly regulated. In the first reaction unique to purine nucleotide biosynthesis, PPAT catalyzes the displacement of PRPP's pyrophosphate group (PP i ) by an amide nitrogen donated from either glutamine (N), glycine (N&C), aspartate (N), folic acid (C 1 ), or CO 2 . This

Macromolecule - Misplaced Pages Continue

1856-441: The umami taste, often in the form of a yeast extract. A nucleo tide is composed of three distinctive chemical sub-units: a five-carbon sugar molecule, a nucleobase (the two of which together are called a nucleo side ), and one phosphate group . With all three joined, a nucleotide is also termed a "nucleo side mono phosphate", "nucleoside di phosphate" or "nucleoside tri phosphate", depending on how many phosphates make up

1914-458: The ability to bind a wide range of cofactors and coenzymes , smaller molecules that can endow the protein with specific activities beyond those associated with the polypeptide chain alone. RNA is multifunctional, its primary function is to encode proteins , according to the instructions within a cell's DNA. They control and regulate many aspects of protein synthesis in eukaryotes . RNA encodes genetic information that can be translated into

1972-425: The ability to catalyse biochemical reactions. DNA is an information storage macromolecule that encodes the complete set of instructions (the genome ) that are required to assemble, maintain, and reproduce every living organism. DNA and RNA are both capable of encoding genetic information, because there are biochemical mechanisms which read the information coded within a DNA or RNA sequence and use it to generate

2030-453: The activity of proteins and other signaling molecules, and as enzymatic cofactors , often carrying out redox reactions. Signaling cyclic nucleotides are formed by binding the phosphate group twice to the same sugar molecule , bridging the 5'- and 3'- hydroxyl groups of the sugar. Some signaling nucleotides differ from the standard single-phosphate group configuration, in having multiple phosphate groups attached to different positions on

2088-490: The amino acid sequence of proteins, as evidenced by the messenger RNA molecules present within every cell, and the RNA genomes of a large number of viruses. The single-stranded nature of RNA, together with tendency for rapid breakdown and a lack of repair systems means that RNA is not so well suited for the long-term storage of genetic information as is DNA. In addition, RNA is a single-stranded polymer that can, like proteins, fold into

2146-558: The cell and cell parts (both internally and intercellularly), cell division, etc.. In addition, nucleotides participate in cell signaling ( cyclic guanosine monophosphate or cGMP and cyclic adenosine monophosphate or cAMP) and are incorporated into important cofactors of enzymatic reactions (e.g., coenzyme A , FAD , FMN , NAD , and NADP ). In experimental biochemistry , nucleotides can be radiolabeled using radionuclides to yield radionucleotides. 5-nucleotides are also used in flavour enhancers as food additive to enhance

2204-411: The diet and are also synthesized from common nutrients by the liver . Nucleotides are composed of three subunit molecules: a nucleobase , a five-carbon sugar ( ribose or deoxyribose ), and a phosphate group consisting of one to three phosphates . The four nucleobases in DNA are guanine , adenine , cytosine , and thymine ; in RNA, uracil is used in place of thymine. Nucleotides also play

2262-409: The eye Macro photography , a type of close-up photography Image macro , a picture with text superimposed Monopole, Astrophysics and Cosmic Ray Observatory (MACRO), a particle physics experiment Macronutrients , classes of chemical compounds humans consume in the largest quantities (i.e., proteins, fats, and carbohydrates) Sociology [ edit ] Macrosociology , sociology at

2320-415: The formation of PRPP . PRPS1 is the enzyme that activates R5P , which is formed primarily by the pentose phosphate pathway , to PRPP by reacting it with ATP . The reaction is unusual in that a pyrophosphoryl group is directly transferred from ATP to C 1 of R5P and that the product has the α configuration about C1. This reaction is also shared with the pathways for the synthesis of Trp , His , and

2378-412: The formation of carbamoyl phosphate from glutamine and CO 2 . Next, aspartate carbamoyltransferase catalyzes a condensation reaction between aspartate and carbamoyl phosphate to form carbamoyl aspartic acid , which is cyclized into 4,5-dihydroorotic acid by dihydroorotase . The latter is converted to orotate by dihydroorotate oxidase . The net reaction is: Orotate is covalently linked with

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2436-485: The individual monomer subunit and total molecular mass . Complicated biomacromolecules, on the other hand, require multi-faceted structural description such as the hierarchy of structures used to describe proteins . In British English , the word "macromolecule" tends to be called " high polymer ". Macromolecules often have unusual physical properties that do not occur for smaller molecules. Another common macromolecular property that does not characterize smaller molecules

2494-407: The intermediate adenylosuccinate. Fumarate is then cleaved off forming adenosine monophosphate. This step is catalyzed by adenylosuccinate lyase. Inosine monophosphate is converted to guanosine monophosphate by the oxidation of IMP forming xanthylate, followed by the insertion of an amino group at C 2 . NAD is the electron acceptor in the oxidation reaction. The amide group transfer from glutamine

2552-401: The national level Macroeconomics , economics at a higher level, above individual markets Macromanagement in business, the idea of "managing from afar" Computing [ edit ] Macro (computer science) , a set of instructions that is represented in an abbreviated format Macro instruction , a statement, typically for an assembler, that invokes a macro definition to generate

2610-422: The nucleotide monomers of a nucleic acid end-to-end into a long chain. These chain-joins of sugar and phosphate molecules create a 'backbone' strand for a single- or double helix . In any one strand, the chemical orientation ( directionality ) of the chain-joins runs from the 5'-end to the 3'-end ( read : 5 prime-end to 3 prime-end)—referring to the five carbon sites on sugar molecules in adjacent nucleotides. In

2668-415: The phosphate group. In nucleic acids , nucleotides contain either a purine or a pyrimidine base—i.e., the nucleobase molecule, also known as a nitrogenous base—and are termed ribo nucleotides if the sugar is ribose, or deoxyribo nucleotides if the sugar is deoxyribose. Individual phosphate molecules repetitively connect the sugar-ring molecules in two adjacent nucleotide monomers, thereby connecting

2726-478: The purine and pyrimidine bases. Thus a reaction network towards the purine and pyrimidine RNA building blocks can be established starting from simple atmospheric or volcanic molecules. An unnatural base pair (UBP) is a designed subunit (or nucleobase ) of DNA which is created in a laboratory and does not occur in nature. Examples include d5SICS and dNaM . These artificial nucleotides bearing hydrophobic nucleobases , feature two fused aromatic rings that form

2784-485: The purine ring proceeds by a 10-step pathway to the branch-point intermediate IMP , the nucleotide of the base hypoxanthine . AMP and GMP are subsequently synthesized from this intermediate via separate, two-step pathways. Thus, purine moieties are initially formed as part of the ribonucleotides rather than as free bases . Six enzymes take part in IMP synthesis. Three of them are multifunctional: The pathway starts with

2842-528: The pyrimidine bases thymine (in DNA) and uracil (in RNA) occur in just one. Adenine forms a base pair with thymine with two hydrogen bonds, while guanine pairs with cytosine with three hydrogen bonds. In addition to being building blocks for the construction of nucleic acid polymers, singular nucleotides play roles in cellular energy storage and provision, cellular signaling, as a source of phosphate groups used to modulate

2900-403: The ribosylation and decarboxylation reactions, forming UMP from orotic acid in the presence of PRPP. It is from UMP that other pyrimidine nucleotides are derived. UMP is phosphorylated by two kinases to uridine triphosphate (UTP) via two sequential reactions with ATP. First, the diphosphate from UDP is produced, which in turn is phosphorylated to UTP. Both steps are fueled by ATP hydrolysis: CTP

2958-407: The ring synthesis occurs. For reference, the syntheses of the purine and pyrimidine nucleotides are carried out by several enzymes in the cytoplasm of the cell, not within a specific organelle . Nucleotides undergo breakdown such that useful parts can be reused in synthesis reactions to create new nucleotides. The synthesis of the pyrimidines CTP and UTP occurs in the cytoplasm and starts with

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3016-471: The sugar. Nucleotide cofactors include a wider range of chemical groups attached to the sugar via the glycosidic bond , including nicotinamide and flavin , and in the latter case, the ribose sugar is linear rather than forming the ring seen in other nucleotides. Nucleotides can be synthesized by a variety of means, both in vitro and in vivo . In vitro, protecting groups may be used during laboratory production of nucleotides. A purified nucleoside

3074-475: The term macromolecule as used in polymer science refers only to a single molecule. For example, a single polymeric molecule is appropriately described as a "macromolecule" or "polymer molecule" rather than a "polymer," which suggests a substance composed of macromolecules. Because of their size, macromolecules are not conveniently described in terms of stoichiometry alone. The structure of simple macromolecules, such as homopolymers, may be described in terms of

3132-403: The term to describe large molecules varies among the disciplines. For example, while biology refers to macromolecules as the four large molecules comprising living things, in chemistry , the term may refer to aggregates of two or more molecules held together by intermolecular forces rather than covalent bonds but which do not readily dissociate. According to the standard IUPAC definition,

3190-468: The tunability of properties and/or responsive behavior as for instance in smart inorganic polymers . macro-#Prefix (Redirected from Macro- ) [REDACTED] Look up macro  or macro- in Wiktionary, the free dictionary. Macro (or MACRO ) may refer to: Science and technology [ edit ] Macroscopic , subjects visible to

3248-438: The two complementary strands of the double helix . In contrast, both RNA and proteins are normally single-stranded. Therefore, they are not constrained by the regular geometry of the DNA double helix, and so fold into complex three-dimensional shapes dependent on their sequence. These different shapes are responsible for many of the common properties of RNA and proteins, including the formation of specific binding pockets , and

3306-431: Was coined by Nobel laureate Hermann Staudinger in the 1920s, although his first relevant publication on this field only mentions high molecular compounds (in excess of 1,000 atoms). At that time the term polymer , as introduced by Berzelius in 1832, had a different meaning from that of today: it simply was another form of isomerism for example with benzene and acetylene and had little to do with size. Usage of

3364-548: Was governed by physico-chemical processes. RNA is composed of purine and pyrimidine nucleotides, both of which are necessary for reliable information transfer, and thus Darwinian evolution . Becker et al. showed how pyrimidine nucleosides can be synthesized from small molecules and ribose , driven solely by wet-dry cycles. Purine nucleosides can be synthesized by a similar pathway. 5'-mono- and di-phosphates also form selectively from phosphate-containing minerals, allowing concurrent formation of polyribonucleotides with both

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