title: Improved poly-gamma-glutamic acid production by chromosomal integration of the Vitreoscilla hemoglobin gene (vgb) in Bacillus subtilis.
abstract: In order to alleviate oxygen limitation and improve the yield of poly-gamma-glutamic acid (gamma-PGA) during fermentation, the Vitreoscilla hemoglobin gene (vgb) was integrated into the chromosome of Bacillus subtilis and expressed during gamma-PGA production. The activity of the expressed Vitreoscilla hemoglobin (VHb) was confirmed by CO-difference spectrum. Expression of VHb enhanced cell growth under high viscosity fermentation conditions 1.26-fold and increased the yield of gamma-PGA 2.07-fold. These results indicate that the expression of VHb could be advantageous in high viscosity fermentation media.
authors.affiliation: Shandong Academy of Pharmaceutical Science, Jinan 250101, PR China.
authors.forename: Yishan
authors.initials: Y
authors.lastname: Su
authors.forename: Xia
authors.initials: X
authors.lastname: Li
authors.forename: Qingzhi
authors.initials: Q
authors.lastname: Liu
authors.forename: Zhongwen
authors.initials: Z
authors.lastname: Hou
authors.forename: Xiqiang
authors.initials: X
authors.lastname: Zhu
authors.forename: Xueping
authors.initials: X
authors.lastname: Guo
authors.forename: Peixue
authors.initials: P
authors.lastname: Ling
mesh_terms: D001412:Bacillus subtilis / Q000254:growth & development / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics*; D002876:Chromosomes, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics*; D016254:Mutagenesis, Insertional / Q000235:genetics*; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D016133:Polymerase Chain Reaction; D015203:Reproducibility of Results; D013057:Spectrum Analysis; D013997:Time Factors; D014170:Transformation, Genetic; D054793:Truncated Hemoglobins / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D054793:Truncated Hemoglobins; C511775:poly(gamma-glutamic acid); C082613:hemoglobin protein, Vitreoscilla; D011099:Polyglutamic Acid