缺陷短波单胞菌高产L-脯氨酸菌株的选育及其发酵条件优化

摘要

Brevundimonas diminuta JNPP-1 was used as the original strain for stepwise mutation by ultraviolet (UV) and N-methyl-N-nitro-N-nitrosoguanidine (NTG) treatments. A stable and L-proline overproducing mutant JNPP-NSS (SGr、Sucg、NaClr) was obtained. Through the optimization of batch fermentation condition, the maximum concentration of L-proline reached 47. 3 g/L, which was 45. 1% higher than that of the original strain, and the production rate was increased from 0. 45 to 0. 78 g/ ( L · h) .%以缺陷短波单胞菌(Brevundimonas diminuta)JNPP-1为出发菌株,利用紫外诱变及亚硝基胍复合诱变的方式,获得1株遗传性能稳定、可抗磺胺胍、能耐高渗透压以及能以琥珀酸钠为唯一C源的、在培养基上有生长优势的L-脯氨酸高产菌株JNPP-NSS( SGr、Sucg、NaClr).经发酵条件优化后,L-脯氨酸的最高质量浓度可达47.3 g/L,与出发菌株相比提高了45.1％,生产速率由0.45 g/(L·h)提高到0.78 g/(L·h).