monopeptides

A monopeptide is a molecule consisting of a single amino acid residue. In biochemical nomenclature, the term "peptide" traditionally refers to a chain of two or more amino acids linked by peptide bonds. Therefore, a monopeptide is technically not a peptide in the conventional sense, as it lacks the defining peptide bond linkage. However, the term is sometimes used for convenience or in specific contexts to refer to a single amino acid that might be considered in isolation, perhaps as a building block or a very simple functional unit.

Amino acids are the fundamental building blocks of proteins. Each amino acid has a central carbon atom bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom, and a unique side chain (R group). When two or more amino acids join together, they form a peptide chain through a dehydration reaction that creates a peptide bond between the carboxyl group of one amino acid and the amino group of another.

While the term "monopeptide" is not standard in mainstream peptide and protein chemistry, it might appear in discussions about amino acid metabolism, signaling pathways where individual amino acids play roles, or in the context of artificial chemical synthesis where a single amino acid unit is being manipulated. In most scientific literature, a single amino acid is simply referred to as an "amino acid."