Search results
Results from the WOW.Com Content Network
In biochemistry, a zymogen (/ ˈ z aɪ m ə dʒ ən,-m oʊ-/ [1] [2]), also called a proenzyme (/ ˌ p r oʊ ˈ ɛ n z aɪ m / [3] [4]), is an inactive precursor of an enzyme.A zymogen requires a biochemical change (such as a hydrolysis reaction revealing the active site, or changing the configuration to reveal the active site) for it to become an active enzyme.
Histamine N-methyltransferase is encoded by a single gene, called HNMT, which has been mapped to chromosome 2 in humans. [5]Three transcript variants have been identified for this gene in humans, which produce different protein isoforms [6] [5] due to alternative splicing, which allows a single gene to code for multiple proteins by including or excluding particular exons of a gene in the final ...
In order to prevent inappropriate or premature activation of the digestive enzymes (they may, for example, trigger pancreatic self-digestion causing pancreatitis), these enzymes are secreted as inactive zymogen. The precursor of pepsin, pepsinogen, is
The mevalonate pathway (MVA pathway or HMG-CoA reductase pathway) and the MEP pathway are metabolic pathways for the biosynthesis of isoprenoid precursors: IPP and DMAPP. Whereas plants use both MVA and MEP pathway, most organisms only use one of the pathways for the biosynthesis of isoprenoid precursors.
When several consecutive enzymes of a metabolic pathway channel substrates between themselves, [2] this is called a metabolon. [3] Channeling can make a metabolic pathway more rapid and efficient than it would be if the enzymes were randomly distributed in the cytosol , or prevent the release of unstable intermediates. [ 4 ]
Proteins catabolize into amino acids, and amino acids are precursors for purines, nucleotides and nucleosides which are used in the purine nucleotide cycle. [7] The amino acid glutamate is used to neutralize the ammonia produced when AMP is converted into IMP. Another amino acid, aspartate, is used along with IMP to produce S-AMP in the cycle ...
Phosphoenolpyruvate carboxykinase (EC 4.1.1.32, PEPCK) is an enzyme in the lyase family used in the metabolic pathway of gluconeogenesis. It converts oxaloacetate into phosphoenolpyruvate and carbon dioxide. [1] [2] [3] It is found in two forms, cytosolic and mitochondrial.
Starvation response in animals (including humans) is a set of adaptive biochemical and physiological changes, triggered by lack of food or extreme weight loss, in which the body seeks to conserve energy by reducing metabolic rate and/or non-resting energy expenditure to prolong survival and preserve body fat and lean mass.