Propargylglycine
Propargylglycine is a non-proteinogenic [amino acid] found in a variety of organisms including Amanita mushrooms and the bacteria Streptomyces cattleya. It is a toxin that interferes with the metabolism of sulfur-containing amino acids via inhibition of cystathionine γ-lyase.
Structure and properties
Propargylglycine is a is non-proteinogenic amino acid that features an unusual terminal alkyne group. It is chemically related to β-ethynylserine, with which it shares a biosynthetic pathway, and to cyanoalanine. Propargylglycine is useful in click chemistry applications.Biological activity
Propargylglycine acts as an irreversible inhibitor of cystathionine γ-lyase, an enzyme that catalyzes the breakdown of cystathionine to cysteine and is involved in the endogenous production of hydrogen sulfide. It functions as a mechanism-based inactivator, forming a covalent adduct with the enzyme's pyridoxal 5'-phosphate cofactor. Due to its inhibition of CSE, propargylglycine is widely used as a research tool to study the biological roles of H2S in processes such as vasodilation, inflammation, oxidative stress, and various disease models.It also inhibits other PLP-dependent enzymes such as methionine γ-lyase and alanine transaminase.