The Enzyme Commission number ( EC number ) is a numerical classification scheme for enzymes , based on the chemical reactions they catalyze . As a system of enzyme nomenclature , every EC number is associated with a recommended name for the corresponding enzyme-catalyzed reaction.
22-447: PDH may refer to: Angiotensin-converting enzyme , an enzyme Plesiochronous digital hierarchy , in telecommunications networks Pound–Drever–Hall technique for stabilizing a laser's output Pyranose dehydrogenase (acceptor) , an enzyme Pyruvate dehydrogenase , an enzyme Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with
44-522: A function of N domain portion on the ACE enzyme. ACE inhibitors that cross the blood–brain barrier and have preferentially selected N-terminal activity may therefore cause accumulation of Aβ42 and progression of dementia. ACE inhibitors are widely used as pharmaceutical drugs in the treatment of conditions such as high blood pressure , heart failure , diabetic nephropathy , and type 2 diabetes mellitus . ACE inhibitors inhibit ACE competitively. That results in
66-590: Is a central component of the renin–angiotensin system (RAS), which controls blood pressure by regulating the volume of fluids in the body. It converts the hormone angiotensin I to the active vasoconstrictor angiotensin II . Therefore, ACE indirectly increases blood pressure by causing blood vessels to constrict. ACE inhibitors are widely used as pharmaceutical drugs for treatment of cardiovascular diseases . Other lesser known functions of ACE are degradation of bradykinin , substance P and amyloid beta-protein . ACE
88-406: Is a potent vasoconstrictor in a substrate concentration-dependent manner. Angiotensin II binds to the type 1 angiotensin II receptor (AT1) , which sets off a number of actions that result in vasoconstriction and therefore increased blood pressure. ACE is also part of the kinin–kallikrein system where it degrades bradykinin , a potent vasodilator , and other vasoactive peptides. Kininase II
110-467: Is also known by the following names: ACE hydrolyzes peptides by the removal of a dipeptide from the C-terminus. Likewise it converts the inactive decapeptide angiotensin I to the octapeptide angiotensin II by removing the dipeptide His-Leu. ACE is a central component of the renin–angiotensin system (RAS), which controls blood pressure by regulating the volume of fluids in the body. Angiotensin II
132-629: Is different from the 'FORMAT NUMBER' Oxidation /reduction reactions; transfer of H and O atoms or electrons from one substance to another Similarity between enzymatic reactions can be calculated by using bond changes, reaction centres or substructure metrics (formerly EC-BLAST], now the EMBL-EBI Enzyme Portal). Before the development of the EC number system, enzymes were named in an arbitrary fashion, and names like old yellow enzyme and malic enzyme that give little or no clue as to what reaction
154-408: Is expressed in many tissues, mainly in the lung, including vascular endothelial cells, epithelial kidney cells, and testicular Leydig cells , whereas the germinal is expressed only in sperm . Brain tissue has ACE enzyme, which takes part in local RAS and converts Aβ42 (which aggregates into plaques) to Aβ40 (which is thought to be less toxic) forms of beta amyloid . The latter is predominantly
176-440: Is still highly debated. Alzheimer patients usually show higher ACE levels in their brain. Some studies suggest that ACE inhibitors that are able to pass the blood-brain-barrier (BBB) could enhance the activity of major amyloid-beta peptide degrading enzymes like neprilysin in the brain resulting in a slower development of Alzheimer's disease. More recent research suggests that ACE inhibitors can reduce risk of Alzheimer's disease in
198-420: Is the same as angiotensin-converting enzyme. Thus, the same enzyme (ACE) that generates a vasoconstrictor (ANG II) also disposes of vasodilators (bradykinin). ACE is a zinc metalloproteinase . The zinc center catalyses the peptide hydrolysis. Reflecting the critical role of zinc, ACE can be inhibited by metal -chelating agents. The E384 residue is mechanistically critical. As a general base, it deprotonates
220-603: The zinc-bound water , producing a nucleophilic Zn-OH center. The resulting ammonium group then serves as a general acid to cleave the C-N bond. The function of the chloride ion is very complex and is highly debated. The anion activation by chloride is a characteristic feature of ACE. It was experimentally determined that the activation of hydrolysis by chloride is highly dependent on the substrate. While it increases hydrolysis rates for e.g. Hip-His-Leu it inhibits hydrolysis of other substrates like Hip-Ala-Pro. Under physiological conditions
242-497: The ACE for D-allele carriers, hence higher capacity to produce angiotensin II, the blood pressure will increase sooner than for I-allele carriers. This results in a lower maximal heart rate and lower maximum oxygen uptake (VO 2max ). Therefore, D-allele carriers have a 10% increased risk of cardiovascular diseases. Furthermore, the D-allele is associated with a greater increase in left ventricular growth in response to training compared to
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#1732844783870264-498: The I-allele. On the other hand, I-allele carriers usually show an increased maximal heart rate due to lower ACE levels, higher maximum oxygen uptake and therefore show an enhanced endurance performance. The I allele is found with increased frequency in elite distance runners, rowers and cyclists. Short distance swimmers show an increased frequency of the D-allele, since their discipline relies more on strength than endurance. The enzyme
286-689: The International Congress of Biochemistry in Brussels set up the Commission on Enzymes under the chairmanship of Malcolm Dixon in 1955. The first version was published in 1961, and the Enzyme Commission was dissolved at that time, though its name lives on in the term EC Number . The current sixth edition, published by the International Union of Biochemistry and Molecular Biology in 1992 as
308-888: The absence of apolipoprotein E4 alleles (ApoE4) , but will have no effect in ApoE4- carriers. Another more recent hypothesis is that higher levels of ACE can prevent Alzheimer's. It is assumed that ACE can degrade beta-amyloid in brain blood vessels and therefore help prevent the progression of the disease. A negative correlation between the ACE1 D-allele frequency and the prevalence and mortality of COVID-19 has been established. The angiotensin converting enzyme gene has more than 160 polymorphisms described as of 2018. Studies have shown that different genotypes of angiotensin converting enzyme can lead to varying influence on athletic performance. However, these data should be interpreted with caution due to
330-513: The decreased formation of angiotensin II and decreased metabolism of bradykinin , which leads to systematic dilation of the arteries and veins and a decrease in arterial blood pressure. In addition, inhibiting angiotensin II formation diminishes angiotensin II-mediated aldosterone secretion from the adrenal cortex , leading to a decrease in water and sodium reabsorption and a reduction in extracellular volume. ACE's effect on Alzheimer's disease
352-403: The enzyme reaches about 60% of its maximal activity toward angiotensin I while it reaches its full activity toward bradykinin. It is therefore assumed that the function of the anion activation in ACE provides high substrate specificity. Other theories say that the chloride might simply stabilize the overall structure of the enzyme. The ACE gene, ACE , encodes two isozymes . The somatic isozyme
374-417: The letters "EC" followed by four numbers separated by periods. Those numbers represent a progressively finer classification of the enzyme. Preliminary EC numbers exist and have an 'n' as part of the fourth (serial) digit (e.g. EC 3.5.1.n3). For example, the tripeptide aminopeptidases have the code "EC 3.4.11.4", whose components indicate the following groups of enzymes: NB:The enzyme classification number
396-469: The relatively small size of the investigated groups. The rs1799752 I/D polymorphism (aka rs4340, rs13447447, rs4646994) consists of either an insertion (I) or deletion (D) of a 287 base pair sequence in intron 16 of the gene. The DD genotype is associated with higher plasma levels of the ACE protein, the DI genotype with intermediate levels, and II with lower levels. During physical exercise, due to higher levels of
418-419: The same reaction, then they receive the same EC number. Furthermore, through convergent evolution , completely different protein folds can catalyze an identical reaction (these are sometimes called non-homologous isofunctional enzymes ) and therefore would be assigned the same EC number. By contrast, UniProt identifiers uniquely specify a protein by its amino acid sequence. Every enzyme code consists of
440-1032: The title PDH . 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=PDH&oldid=1252964012 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Angiotensin-converting enzyme 1O86 , 1O8A , 1UZE , 1UZF , 2C6F , 2C6N , 2IUL , 2IUX , 2OC2 , 2XY9 , 2XYD , 2YDM , 3BKK , 3BKL , 3NXQ , 4APH , 4APJ , 3L3N , 4BXK , 4BZR , 4BZS , 4C2N , 4C2O , 4C2P , 4C2Q , 4C2R , 4CA5 , 4CA6 , 4UFA , 4UFB , 5AMB , 5AM9 , 5AM8 , 5AMC , 5AMA 1636 11421 ENSG00000159640 ENSMUSG00000020681 P12821 P09470 NM_001382701 NM_001382702 NM_009598 NM_207624 NM_001281819 NP_001369631 NP_001268748 NP_033728 NP_997507 Angiotensin-converting enzyme ( EC 3.4.15.1 ), or ACE ,
462-457: Was catalyzed were in common use. Most of these names have fallen into disuse, though a few, especially proteolyic enzymes with very low specificity, such as pepsin and papain , are still used, as rational classification on the basis of specificity has been very difficult. By the 1950s the chaos was becoming intolerable, and after Hoffman-Ostenhof and Dixon and Webb had proposed somewhat similar schemes for classifying enzyme-catalyzed reactions,
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#1732844783870484-503: Was reported by Leonard T. Skeggs Jr. in 1956. The crystal structure of human testis ACE was solved in the year 2002 by Ramanathan Natesh, Sylva Schwager, and Edward Sturrock in the lab of K. Ravi Acharya. It is located mainly in the capillaries of the lungs but can also be found in endothelial and kidney epithelial cells . Enzyme Commission number EC numbers do not specify enzymes but enzyme-catalyzed reactions. If different enzymes (for instance from different organisms) catalyze
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