α-amino acid analogues as mechanism-based inactivators of γ-aminobutyric acid aminotransferase

γ- and β-Amino acids have been used previously to inactivate γ-aminobutyric acid aminotransferase. Here it is shown that β-halo, β-phospho-, β-sulpho-L-alanine, and vinyl-L-glycine, all α-amino acids, are time dependent inactivators of purified γ-aminobutyrate aminotransferase. Observations that this inactivation is stereospecific and requires the formation of a Michaelis complex support a catalytic mechanism for this process.