title: [Effects of metal ions on gamma-poly (glutamic acid) synthesis by Bacillus licheniformis].
abstract: In the course of gamma-poly (glutamic acid) gamma-PGA fermentation, metal ions K+, Mg2+, Fe3+, Ca2+, Mo6+, Mn2+, Co2+ and Zn2+ in the medium have certain effects on the synthesis of gamma-poly(glutamic acid). Excess or lack of K+, Mg2+ and Fe3+ results in reduced yield of gamma-PGA. It was found that the gamma-PGA synthesis by Bacillus licheniformis was promoted obviously by Ca2+ and Mo6+. Synthesis and stereochemical composition of gamma-PGA was greatly regulated by Mn2+. gamma-PGA was not produced without Mn2+ in medium, and with the increase of Zn2+ concentration the yield of gamma-PGA and the proportion of D-glutamic acid in the peptide increase. Regulative effect of Co2+ and Zn2+ was almost the same as that of Mn2+, thus the combination of Mn2+, Co2+ cannot enhance gamma-PGA synthesis and affect stereochemical composition of gamma-PGA. Based on the experimental date, an appropriate formulation of metal ions in the medium for gamma-PGA production was obtained.
authors.affiliation: Key Lab. of Industrial Biotechnology, Ministry of Education, Southern Yantze University, Wuxi 214036, China.
authors.forename: G
authors.initials: G
authors.lastname: Yang
authors.forename: J
authors.initials: J
authors.lastname: Chen
authors.forename: Y B
authors.initials: YB
authors.lastname: Qu
authors.forename: S Y
authors.initials: SY
authors.lastname: Lun
mesh_terms: D001407:Bacillus / Q000187:drug effects* / Q000378:metabolism; D002118:Calcium / Q000494:pharmacology; D003035:Cobalt / Q000494:pharmacology; D003470:Culture Media / Q000378:metabolism / Q000494:pharmacology; D005285:Fermentation / Q000187:drug effects / Q000502:physiology; D018698:Glutamic Acid / Q000096:biosynthesis*; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008968:Molecular Conformation; D008982:Molybdenum / Q000494:pharmacology; D011099:Polyglutamic Acid / Q000096:biosynthesis*; D011188:Potassium / Q000494:pharmacology; D015032:Zinc / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D011099:Polyglutamic Acid; D003035:Cobalt; D018698:Glutamic Acid; D008345:Manganese; D008982:Molybdenum; D008274:Magnesium; D015032:Zinc; D011188:Potassium; D002118:Calcium