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Characterization of lysine acetylation of a phosphoenolpyruvate carboxylase involved in glutamate overproduction in C orynebacterium glutamicum
Author(s) -
NaganoShoji Megumi,
Hamamoto Yuma,
Mizuno Yuta,
Yamada Ayuka,
Kikuchi Masaki,
Shirouzu Mikako,
Umehara Takashi,
Yoshida Minoru,
Nishiyama Makoto,
Kosono Saori
Publication year - 2017
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/mmi.13658
Subject(s) - phosphoenolpyruvate carboxylase , corynebacterium glutamicum , overproduction , biochemistry , biology , lysine , acetylation , glutamate receptor , glutamate dehydrogenase , enzyme , amino acid , receptor , gene
Summary Protein N ε‐acylation is emerging as a ubiquitous post‐translational modification. In Corynebacterium glutamicum , which is utilized for industrial production of l ‐glutamate, the levels of protein acetylation and succinylation change drastically under the conditions that induce glutamate overproduction. Here, the acylation of phosphoenolpyruvate carboxylase (PEPC), an anaplerotic enzyme that supplies oxaloacetate for glutamate overproduction was characterized. It was shown that acetylation of PEPC at lysine 653 decreased enzymatic activity, leading to reduced glutamate production. An acetylation‐mimic (KQ) mutant of K653 showed severely reduced glutamate production, while the corresponding KR mutant showed normal production levels. Using an acetyllysine‐incorporated PEPC protein, we verified that K653‐acetylation negatively regulates PEPC activity. In addition, NCgl0616, a sirtuin‐type deacetylase, deacetylated K653‐acetylated PEPC in vitro . Interestingly, the specific activity of PEPC was increased during glutamate overproduction, which was blocked by the K653R mutation or deletion of sirtuin‐type deacetylase homologues. These findings suggested that deacetylation of K653 by NCgl0616 likely plays a role in the activation of PEPC, which maintains carbon flux under glutamate‐producing conditions. PEPC deletion increased protein acetylation levels in cells under glutamate‐producing conditions, supporting the hypothesis that PEPC is responsible for a large carbon flux change under glutamate‐producing conditions.