betaalanyl1methylhistidine

Betaalanyl1methylhistidine, commonly known as anserine, is a dipeptide consisting of beta-alanine linked to 1-methylhistidine. It is one of the histidine-containing dipeptides found in animal tissues and is defined by the systematic name beta-alanyl-1-methylhistidine.

Occurrence and sources: Anserine is detected in skeletal muscle and brain tissue of many vertebrates, including humans. Its levels vary with species, tissue type, age, diet, and physical activity. It is related to carnosine, another beta-alanyl dipeptide, but contains a methylated form of histidine.

Biosynthesis and structure: The molecule comprises beta-alanine bound to 1-methylhistidine via a standard peptide bond. It is formed in vivo by peptide synthetases that couple beta-alanine to histidine derivatives, with 1-methylhistidine serving as the histidine component. The imidazole ring of the histidine moiety carries a methyl group at the N1 position, giving rise to the 1-methylhistidine residue.

Biological roles and properties: As a histidine-containing dipeptide, anserine is thought to contribute to pH buffering in muscle during high-intensity exercise and to possess antioxidant properties. It may also participate in metal ion chelation and protection against glycation, though the extent of these effects is less well characterized than for carnosine. Anserine is not considered an essential nutrient.

Metabolism and analysis: Anserine can be hydrolyzed by dipeptidases to yield beta-alanine and 1-methylhistidine, which are then further metabolized or excreted. It can be detected and quantified in tissue and body fluids using analytical techniques such as high-performance liquid chromatography and mass spectrometry, aiding research on muscle biochemistry and nutrition.