PH-dependent regulation of an acidophilic O-acetylhomoserine sulfhydrylase from Lactobacillus plantarum.

ABSTRACT: Bacteria have two routes for the l-methionine biosynthesis. In one route called the direct sulfuration pathway, acetylated l-homoserine is directly converted into l-homocysteine. The reaction using H₂S as the second substrate is catalyzed by a pyridoxal 5'-phosphate-dependent enzyme, O-acetylhomoserine sulfhydrylase (OAHS). In the present study, we determined the enzymatic functions and the structures of OAHS from Lactobacillus plantarum (LpOAHS). The LpOAHS enzyme exhibited the highest catalytic activity under the weak acidic pH condition. In addition, crystallographic analysis revealed that the enzyme takes two distinct structures, open and closed forms. In the closed form, two acidic residues are sterically clustered. The proximity may cause the el

SUBMITTER: Matoba Y 

PROVIDER: S-EPMC11107162 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature