title: Cloning and Expression of the γ-Polyglutamic Acid Synthetase Gene pgsBCA in Bacillus subtilis WB600.
abstract: To clone and express the γ-polyglutamic acid (γ-PGA) synthetase gene pgsBCA in Bacillus subtilis, a pWB980 plasmid was used to construct and transfect the recombinant expression vector pWB980-pgsBCA into Bacillus subtilis WB600. PgsBCA was expressed under the action of a P43 promoter in the pWB980 plasmid. Our results showed that the recombinant bacteria had the capacity to synthesize γ-PGA. The expression product was secreted extracellularly into the fermentation broth, with a product yield of 1.74 g/L or higher. γ-PGA samples from the fermentation broth were purified and characterized. Hydrolysates of γ-PGA presented in single form, constituting simple glutamic acid only, which matched the characteristics of the infrared spectra of the γ-PGA standard, and presented as multimolecular aggregates with a molecular weight within the range of 500-600 kDa. Expressing the γ-PGA synthetase gene pgsBCA in B. subtilis system has potential industrial applications.
authors.affiliation: College of Life Science, Longyan University, Longyan 364012, China; Fujian Provincial Key Laboratory of Preventive Veterinary Medicine and Veterinary Biotechnology, Longyan University, Longyan 364012, China.
authors.forename: Biaosheng
authors.initials: B
authors.lastname: Lin
authors.affiliation: College of Life Science, Longyan University, Longyan 364012, China.
authors.forename: Zhijuan
authors.initials: Z
authors.lastname: Li
authors.affiliation: College of Life Science, Longyan University, Longyan 364012, China.
authors.forename: Huixia
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Life Science, Longyan University, Longyan 364012, China.
authors.forename: Jiangwen
authors.initials: J
authors.lastname: Wu
authors.affiliation: College of Life Science, Longyan University, Longyan 364012, China.
authors.forename: Maochun
authors.initials: M
authors.lastname: Luo
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics*; D005285:Fermentation; D015964:Gene Expression Regulation, Bacterial; D010453:Peptide Synthases / Q000096:biosynthesis / Q000235:genetics*; D010957:Plasmids / Q000096:biosynthesis / Q000235:genetics
chemical_list: D010453:Peptide Synthases; C445299:gamma-polyglutamic acid synthetase