Inhibition of α-aminoadipate-semialdehyde dehydrogenase from Trichosporon adeninovorans bvy lysine and lysine analogues

Abstract

The α-aminoadipate-semialdehyde dehydrogenase (EC 1.2.1.31) of Trichosporon adeninovorans, an enzyme of lysine biosynthesis, was partially purified, some properties of the enzyme were studied and a novel regulatory pattern was found. The K m values of the enzyme were estimated to be 0.78 mM for α-aminoadipate, 1.0 mM for ATP, 0.23 mM for NADPH and 0.77 mM for MgCl 2. It is demonstrated that the enzyme can be regulated by lysine and lysine analogues. l-Lysine ( K i of 0.09 mM), S-(B- aminoethyl)- l-cysteine ( K i of 0.007 mM and δ-hydroxylysine ( K i of 1.65 mM) inhibited the enzyme activity. The inhibition was competitive with respect to α-aminodipate and non-competitive with respect to both ATP and NADPH.