【摘要】 通过离子注入技术对达托霉素产生菌玫瑰孢链霉菌(Streptomyces roseosporus)Z0327进行诱变选育,使用N+作为离子源,注入能量为20keV,并研究了不同离子注入参数对菌株存活率的影响以及正负突变率的关系,初步探讨N+离子注入对达托霉素生产菌所产生的生物学效应。通过癸酸钠抗性筛选法获得多株遗传稳定性较好的高产突变株,其中突变株M1208发酵单位比出发菌株提高了206%,经发酵工艺研究,100L发酵终效价达到1720mg/L。更多还原

【Abstract】 Streptomyces roseosporus Z0327,the bacterial strain used in the production of daptomycin,was implanted with 15×1013~200×1013 ions/cm2 of 20Kev nitrogen ions(N+) ions.Survival rate of the bacteria at different doses was investigated,and mutagenic effects of ion implantation on the microbe were studied.After breeding under the selection pressure of resistance to sodium decanoate,we obtained a mutant strains capable of increased daptomycin yields.The mutant strain M1208 was genetically stable and,at optimal conditions,had 206% higher daptomycin yield compared to the wild type strain.The fermentation of daptomycin production at optimized conditions was carried out in a 100L fermentor.The concentration of daptomycin reached 1720u,about six times higher than that in the shake flask.更多还原