Search results
Results from the WOW.Com Content Network
Histidine ball and stick model spinning. Histidine (symbol His or H) [2] is an essential amino acid that is used in the biosynthesis of proteins.It contains an α-amino group (which is in the protonated –NH 3 + form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO − form under biological conditions), and an imidazole side chain (which is partially ...
The triad of cytomegalovirus protease [b] uses histidine as both the acid and base triad members. Removing the acid histidine results in only a 10-fold activity loss (compared to >10,000-fold when aspartate is removed from chymotrypsin). This triad has been interpreted as a possible way of generating a less active enzyme to control cleavage ...
The enzyme histidine decarboxylase (EC 4.1.1.22, HDC) is transcribed on chromosome 15, region q21.1-21.2, and catalyzes the decarboxylation of histidine to form histamine. In mammals, histamine is an important biogenic amine with regulatory roles in neurotransmission , gastric acid secretion and immune response .
C. albicans with a deletion of CHK1, the two-component histidine kinase gene, show defects in morphogenesis and a drastic decrease in the cell’s ability to resist elimination by human neutrophils. As humans lack this two-component system, it may be a good target for anti-microbial agents in order to treat candidiasis .
The histidine phosphotransfer function can be carried out by proteins with at least two different architectures, both composed of a four-helix bundle but differing in the way the bundle is assembled. Most structurally characterized HPt proteins, such as the Hpt domain from the Escherichia coli protein ArcB and the Saccharomyces cerevisiae ...
Imidazole is the side chain of histidine and is typically used at a concentration of 150 - 500 mM for elution. Histidine or histamine can also be used. Decrease in pH; When the pH decreases, the histidine residue is protonated and can no longer coordinate the metal tag, allowing the protein to be eluted.
Carnosine (beta-alanyl-L-histidine) is a dipeptide molecule, made up of the amino acids beta-alanine and histidine. It is highly concentrated in muscle and brain tissues. [citation needed] Carnosine was discovered by Russian chemist Vladimir Gulevich. [1] Carnosine is naturally produced by the body in the liver [2] from beta-alanine and histidine.
Aminopeptidases are a diverse group of enzymes that play crucial roles in various biological processes, including protein digestion, cell growth, and immune response.They are classified based on their substrate specificity (strength of binding) and catalytic mechanism (means of catalyzing their reaction) into two main categories: metalloaminopeptidases and cysteine aminopeptidases.