Search results
Results from the WOW.Com Content Network
SIRT4 is a mitochondrial ADP-ribosyltransferase that inhibits mitochondrial glutamate dehydrogenase 1 activity, thereby downregulating insulin secretion in response to amino acids. [7] A deacetylation of malonyl-CoA decarboxylase enzyme by SIRT4 represses the enzyme activity, inhibiting fatty acid oxidation in muscle and liver cells.
The first sirtuin was identified in yeast (a lower eukaryote) and named sir2. In more complex mammals, there are seven known enzymes that act in cellular regulation, as sir2 does in yeast. These genes are designated as belonging to different classes (I-IV), depending on their amino acid sequence structure. [20]
SIRT3 is a soluble protein located in the mitochondrial matrix, and contains a mitochondrial processing peptide at the N-terminus.A set of crystal structures of human SIRT3 have been solved, including an apo-structure with no substrate, a structure with a peptide containing acetyl lysine of its natural substrate acetyl-CoA synthetase 2, a reaction intermediate structure trapped by a thioacetyl ...
β-1,4- N-acetylglucosaminidases (EC 3.2.1.30) split the multimer products, such as di-acetylchitobiose, chitotriose, and chitotetraose, into monomers of N-acetylglucoseamine (GlcNAc). [ 11 ] Chitinases were also classified based on the amino acid sequences, as that would be more helpful in understanding the evolutionary relationships of these ...
Two amino acids have acidic side chains at physiological pH (aspartate or glutamate) and so are the most common members of the acidic triad residue. [3] Cytomegalovirus protease [ b ] uses a pair of histidines, one as the base, as usual, and one as the acid. [ 1 ]
The commercial production of amino acids usually relies on mutant bacteria that overproduce individual amino acids using glucose as a carbon source. Some amino acids are produced by enzymatic conversions of synthetic intermediates. 2-Aminothiazoline-4-carboxylic acid is an intermediate in the industrial synthesis of L-cysteine for example.
Glutamine is the most abundant naturally occurring, nonessential amino acid in the human body, and one of the few amino acids that can directly cross the blood–brain barrier. [8] Humans obtain glutamine through catabolism of proteins in foods they eat. [ 24 ]
Peptide bonds to proline, and to other N-substituted amino acids (such as sarcosine), are able to populate both the cis and trans isomers. Most peptide bonds overwhelmingly adopt the trans isomer (typically 99.9% under unstrained conditions), chiefly because the amide hydrogen ( trans isomer) offers less steric repulsion to the preceding C α ...