Molecular mechanisms and metabolic engineering of glutamate overproduction in Corynebacterium glutamicum.
Glutamate is a commercially important chemical. It is used as a flavor enhancer and is a major raw material for producing industrially useful chemicals. A coryneform bacterium, Corynebacterium glutamicum, was isolated in 1956 by Japanese researchers as a glutamate-overproducing bacterium and since then, remarkable progress in glutamate production has been made using this microorganism. Currently, the global market for glutamate is over 2.5 million tons per year. Glutamate overproduction by C. glutamicum is induced by specific treatments-biotin limitation, addition of fatty acid ester surfactants such as Tween 40, and addition of β-lactam antibiotics such as penicillin. Molecular biology and metabolic engineering studies on glutamate overproduction have revealed that metabolic flow is significantly altered by these treatments. These studies have also provided insight into the molecular mechanisms underlying these changes. In this chapter, we review our current understanding of the molecular mechanisms of glutamate overproduction in C. glutamicum, and we discuss the advances made by metabolic engineering of this microorganism.
Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Takashi
T
Hirasawa
Jongpill
J
Kim
Tomokazu
T
Shirai
Chikara
C
Furusawa
Hiroshi
H
Shimizu
D002952:Citric Acid Cycle / Q000235:genetics; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism*; D018698:Glutamic Acid / Q000096:biosynthesis*; D007656:Ketoglutaric Acids / Q000378:metabolism; D060847:Metabolic Engineering; D053858:Metabolic Networks and Pathways / Q000235:genetics; D043586:Methylmalonyl-CoA Decarboxylase / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits
D007656:Ketoglutaric Acids; D021122:Protein Subunits; D018698:Glutamic Acid; D043586:Methylmalonyl-CoA Decarboxylase