title: Kinetic analysis and modeling of daptomycin batch fermentation by Streptomyces roseosporus.
abstract: In this study, Streptomyces roseosporus was subjected to helium-neon (He-Ne) laser (632.8 nm) irradiation to improve the production ability of extracellular antibiotic daptomycin. Under the optimum irradiation dosage of 18 mW for 22 min, a stable positive mutant strain S. roseosporus LC-54 was obtained. The maximum A21978C (daptomycin is a semisynthetic antimicrobial substance derived from the A21978C complex) yield of this mutant strain was 296 mg/l, which was 146% higher than that of the wild strain. The mutant strain grew more quickly and utilized carbohydrate sources more efficiently than the wild strain. The batch culture kinetics was investigated in a 7 l bioreactor. The logistic equation for growth, the Luedeking-Piret equation for daptomycin production, and Luedeking-Piret-like equations for carbon substrate consumption were established. This model appeared to provide a reasonable description for each parameter during the growth phase and fitted fairly well with the experiment data.
authors.affiliation: Department of Bioengineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Lu
authors.forename: Jinghua
authors.initials: J
authors.lastname: Fan
authors.forename: Jianping
authors.initials: J
authors.lastname: Wen
authors.forename: Zhendong
authors.initials: Z
authors.lastname: Xia
authors.forename: Qinggele
authors.initials: Q
authors.lastname: Caiyin
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D002244:Carbon / Q000378:metabolism; D049109:Cell Proliferation; D017576:Daptomycin / Q000096:biosynthesis*; D005285:Fermentation; D036341:Intercellular Signaling Peptides and Proteins; D007700:Kinetics; D007834:Lasers; D008954:Models, Biological; D009154:Mutation / Q000528:radiation effects; D010455:Peptides / Q000378:metabolism; D013302:Streptomyces / Q000166:cytology / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects
chemical_list: D000900:Anti-Bacterial Agents; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D002244:Carbon; C044687:A 21978C1; D017576:Daptomycin