Department of Bioengineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China.
Appl Biochem Biotechnol. 2011 Feb;163(4):453-62. doi: 10.1007/s12010-010-9053-6. Epub 2010 Aug 31.
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.
在这项研究中，玫瑰色链霉菌被氦氖（He-Ne）激光（632.8nm）照射，以提高细胞外抗生素达托霉素的生产能力。在最佳照射剂量为 18mW 照射 22 分钟的条件下，得到了一株稳定的正突变株 S. roseosporus LC-54。该突变株的 A21978C（达托霉素是一种半合成抗菌物质，来源于 A21978C 复合体）产量最高可达 296mg/L，比野生株高 146%。突变株的生长速度比野生株更快，对碳水化合物源的利用效率也更高。在 7L 生物反应器中对分批培养动力学进行了研究。建立了生长的逻辑方程、达托霉素生产的 Luedeking-Piret 方程以及碳源消耗的 Luedeking-Piret 样方程。该模型似乎为生长阶段的每个参数提供了合理的描述，并且与实验数据拟合得相当好。
