Requirement of de novo synthesis of the OdhI protein in penicillin-induced glutamate production by Corynebacterium glutamicum.
We found that penicillin-induced glutamate production by Corynebacterium glutamicum is inhibited when a de novo protein synthesis inhibitor, chloramphenicol, is added simultaneously with penicillin. When chloramphenicol was added 4 h after penicillin addition, glutamate production was essentially unaffected. (3)H-Leucine incorporation experiments revealed that protein synthesis continued for 1 h after penicillin addition and then gradually decreased. These results suggest that de novo protein synthesis within 4 h of penicillin treatment is required for the induction of glutamate production. To identify the protein(s) necessary for penicillin-induced glutamate production, proteome analysis of penicillin-treated C. glutamicum cells was performed with two-dimensional gel electrophoresis. Of more than 500 proteins detected, the amount of 13 proteins, including OdhI (an inhibitory protein for 2-oxoglutarate dehydrogenase complex), significantly increased upon penicillin treatment. Artificial overexpression of the odhI gene resulted in the decreased specific activity of the 2-oxoglutarate dehydrogenase complex and increased glutamate production without any triggers. These results suggest that the de novo synthesis of OdhI is the necessary factor for penicillin-induced glutamate overproduction by C. glutamicum. Moreover, continuous glutamate production was achieved by overexpression of odhI without any triggers. Thus, the odhI-overexpressing strain of C. glutamicum can be useful for efficient glutamate production.
Kim
Jongpill
J
Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan.
Fukuda
Hirohisa
H
Hirasawa
Takashi
T
Nagahisa
Keisuke
K
Nagai
Kazuo
K
Wachi
Masaaki
M
Shimizu
Hiroshi
H
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002701:Chloramphenicol / Q000494:pharmacology; D048230:Corynebacterium glutamicum / Q000201:enzymology*; D015180:Electrophoresis, Gel, Two-Dimensional; D015870:Gene Expression; D018698:Glutamic Acid / Q000096:biosynthesis*; D010406:Penicillins / Q000378:metabolism*; D020543:Proteome / Q000032:analysis; D013194:Staining and Labeling / Q000379:methods; D015533:Transcriptional Activation; D014316:Tritium / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D010406:Penicillins; D020543:Proteome; D014316:Tritium; D018698:Glutamic Acid; D002701:Chloramphenicol