Tag: Amino acid abundance

Alanine, while one of the most abundant amino acids, is not the most common in proteins, often being ranked second only to leucine in overall frequency. The relative abundance of amino acids in a proteome is a complex biological puzzle, shaped by genetic bias, metabolic costs, and the functional demands placed on proteins.

According to proteomics research, Cysteine is the least abundant amino acid in human proteins, with its prevalence nearly an order of magnitude lower than the most common amino acid, Leucine. This scarcity is not a flaw, but a deliberate feature tied to its unique and highly reactive chemical properties.