title: Efficient Production of γ-Polyglutamic Acid by Bacillus subtilis (natto) in Jar Fermenters.
abstract: The large scale fermentation of γ-polyglutamic acid (γ-PGA) by Bacillus subtilis (natto) was done using a 30-liter jar fermenter. A stable cultivation without foaming could be done with addition of 3% NaCl to the medium. The γ-PGA productivity became higher with increasing speed of agitation and amounts of glutamic acid added to the broth. Finally, we were able to obtain about 35 mg/ml of γ-PGA under the optimum conditions. The glutamic acid added to the medium was efficiently converted into γ-PGA in the stationary phase. To discover the role of l-glutamic acid added to the medium for γ-PGA biosynthesis by Bacillus subtilis (natto), the radioactivity incorporated into γ-PGA from (14)C-l-glutamic acid was measured. As a result, radioactive γ-PGA was detected in the medium. Then, the glutamic acid in the medium was transported into the cells and actually polymerized as the glutamic acid unit of γ-PGA.
authors.affiliation: a Research and Development Division, Kikkoman Corporation , 399 Noda, Noda-shi, Chiba 278 , Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ogawa
authors.affiliation: a Research and Development Division, Kikkoman Corporation , 399 Noda, Noda-shi, Chiba 278 , Japan.
authors.forename: F
authors.initials: F
authors.lastname: Yamaguchi
authors.affiliation: a Research and Development Division, Kikkoman Corporation , 399 Noda, Noda-shi, Chiba 278 , Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yuasa
authors.affiliation: a Research and Development Division, Kikkoman Corporation , 399 Noda, Noda-shi, Chiba 278 , Japan.|b Department of Applied Biological Chemistry, Faculty of Agriculture , Shizuoka University , 836 Ohya, Shizuoka-shi, Shizuoka 422 , Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tahara
keywords: Bacillus subtilis (natto); salvage pathway; γ-polyglutamic acid