Glutamate production by Corynebacterium glutamicum: dependence on the oxoglutarate dehydrogenase inhibitor protein OdhI and protein kinase PknG

Bacteria control the metabolic processes by which they obtain nutrients and energy in order to adapt to the environment. Actinobacteria , one of the largest bacterial phyla of major importance for biotechnology, medicine, and agriculture, developed a unique control process that revolves around a key protein, the protein kinase PknG. Here, we use genetic, biochemical, and structural approaches to study PknG in a system that regulates glutamate production in Corynebacterium glutamicum , a species used for the industrial production of amino acids.

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Characterization of lysine acetylation in the peripheral subunit-binding domain of the E2 subunit of the pyruvate dehydrogenase-2-oxoglutarate dehydrogenase hybrid complex from Corynebacterium glutamicum

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbaa114 ◽

2020 ◽

Vol 85 (4) ◽

pp. 874-881

Author(s):

Ayano Komine-Abe ◽

Naoko Kondo ◽

Shosei Kubo ◽

Hisashi Kawasaki ◽

Makoto Nishiyama ◽

...

Keyword(s):

Corynebacterium Glutamicum ◽

Pyruvate Dehydrogenase ◽

Critical Role ◽

Binding Domain ◽

Lysine Acetylation ◽

Hybrid Complex ◽

Glutamate Production ◽

Accumulation Kinetic ◽

Oxoglutarate Dehydrogenase

ABSTRACT In Corynebacterium glutamicum, pyruvate dehydrogenase (PDH) and 2-oxoglutarate dehydrogenase (ODH) form a unique hybrid complex in which CgE1p and CgE1o are associated with the CgE2–CgE3 subcomplex. We analyzed the role of a lysine acetylation site in the peripheral subunit-binding domain of CgE2 in PDH and ODH functions. Acetylation-mimic substitution at Lys391 of CgE2 severely reduced the interaction of CgE2 with CgE1p and CgE3, but not with CgE1o, indicating the critical role of this residue in the assembly of CgE1p and CgE3 into the complex. It also suggested that Lys391 acetylation inhibited the binding of CgE1p and CgE3 to CgE2, thereby affecting PDH and ODH activities. Interestingly, the CgE2-K391R variant strain showed increased l-glutamate production and reduced pyruvate accumulation. Kinetic analysis suggested that the increased affinity of the K391R variant toward pyruvate might be advantageous for l-glutamate production.

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Effect of lysine succinylation on the regulation of 2-oxoglutarate dehydrogenase inhibitor, OdhI, involved in glutamate production in Corynebacterium glutamicum

Bioscience Biotechnology and Biochemistry ◽

10.1080/09168451.2017.1372182 ◽

2017 ◽

Vol 81 (11) ◽

pp. 2130-2138 ◽

Cited By ~ 6

Author(s):

Ayano Komine-Abe ◽

Megumi Nagano-Shoji ◽

Shosei Kubo ◽

Hisashi Kawasaki ◽

Minoru Yoshida ◽

...

Keyword(s):

Corynebacterium Glutamicum ◽

Lysine Succinylation ◽

Glutamate Production ◽

Oxoglutarate Dehydrogenase

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Altered Metabolic Flux due to Deletion of odhA causes l-Glutamate Overproduction in Corynebacterium glutamicum

Applied and Environmental Microbiology ◽

10.1128/aem.01867-06 ◽

2006 ◽

Vol 73 (4) ◽

pp. 1308-1319 ◽

Cited By ~ 102

Author(s):

Yoko Asakura ◽

Eiichiro Kimura ◽

Yoshihiro Usuda ◽

Yoshio Kawahara ◽

Kazuhiko Matsui ◽

...

Keyword(s):

Fatty Acid ◽

Corynebacterium Glutamicum ◽

Metabolic Flux ◽

Dry Weight ◽

Wild Type ◽

Glutamate Production ◽

Glutamate Dehydrogenase Activity ◽

Tween 40 ◽

Oxoglutarate Dehydrogenase ◽

The Relationship

ABSTRACT l-Glutamate overproduction in Corynebacterium glutamicum, a biotin auxotroph, is induced by biotin limitation or by treatment with certain fatty acid ester surfactants or with penicillin. We have analyzed the relationship between the inductions, 2-oxoglutarate dehydrogenase complex (ODHC) activity, and l-glutamate production. Here we show that a strain deleted for odhA and completely lacking ODHC activity produces l-glutamate as efficiently as the induced wild type (27.8 mmol/g [dry weight] of cells for the ohdA deletion strain compared with only 1.0 mmol/g [dry weight] of cells for the uninduced wild type). This level of production is achieved without any induction or alteration in the fatty acid composition of the cells, showing that l-glutamate overproduction can be caused by the change in metabolic flux alone. Interestingly, the l-glutamate productivity of the odhA-deleted strain is increased about 10% by each of the l-glutamate-producing inductions, showing that the change in metabolic flux resulting from the odhA deletion and the inductions have additive effects on l-glutamate overproduction. Tween 40 was indicated to induce drastic metabolic change leading to l-glutamate overproduction in the odhA-deleted strain. Furthermore, optimizing the metabolic flux from 2-oxoglutarate to l-glutamate by tuning glutamate dehydrogenase activity increased the l-glutamate production of the odhA-deleted strain.

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