title: Enhanced production of poly-γ-glutamic acid by a newly-isolated Bacillus subtilis.
abstract: Application of poly-gamma-glutamic acid (γ-PGA), an unusual macromolecular anionic polypeptide, is limited due to the high cost associated with its low productivity. Screening bacterial strains to find a more efficient producer is one approach to overcome this limitation. Strain MJ80 was isolated as a γ-PGA producer among 1,500 bacterial colonies obtained from soil samples. It was identified as Bacillus subtilis, based on the biochemical and morphological properties and 16S rDNA gene sequencing. It produced γ-PGA from both glutamic acid and soybean powder, identifying it as a facultative glutamic acid-metabolizing bacterium. After optimization of its culture conditions, B. subtilis MJ80 showed γ-PGA productivity of 75.5 and 68.7 g/l in 3 and 300 l jar fermenters for 3 days cultivation, respectively, the highest productivity reported to date, suggesting MJ80 to be a promising strain for γ-PGA production.
authors.affiliation: Division of Applied Bioscience and Biotechnology, Glucosamine Saccharide Materials-National Research Laboratory (GSM-NRL), Institute of Agricultural Science and Technology, Chonnam National University, Gwangju, 500-757, Republic of Korea, jwtfight@hotmail.com.
authors.forename: Wan-Taek
authors.initials: WT
authors.lastname: Ju
authors.forename: Yong-Su
authors.initials: YS
authors.lastname: Song
authors.forename: Woo-Jin
authors.initials: WJ
authors.lastname: Jung
authors.forename: Ro-Dong
authors.initials: RD
authors.lastname: Park
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D018698:Glutamic Acid; D007218:Industrial Microbiology; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D012965:Sodium Chloride; D013213:Starch / Q000378:metabolism; D014508:Urea / Q000378:metabolism
chemical_list: D003470:Culture Media; C511775:poly(gamma-glutamic acid); D011099:Polyglutamic Acid; D018698:Glutamic Acid; D012965:Sodium Chloride; D014508:Urea; D013213:Starch