离子束诱变与连续驯化选育耐毒性产丁醇菌株

利用离子束注入的方法对丁醇发酵菌株拜氏梭菌（Clostridium beijerinckii） NCIMB 8052进行诱变，筛选得到了突变株拜氏梭菌（Clostridium beijerinckii） CN18，相对于出发菌株，该突变株的丁醇产量从9.9 g/L增加至12.8 g/L，提高了29.3%；总溶剂产量从13.4 g/L增加至18.2 g/L，提高了35.8%。该突变菌株连续传代20次，溶剂产量稳定，菌株无明显退化。使用含木质素降解产物的培养基对该菌株进行连续培养驯化，最终获得一株耐木质素降解产物的高产突变株，命名为拜氏梭菌（Clostridium beijerinckii） CN88，其耐受木质素降解产物的质量浓度提高至1.0 g/L。在0.6 g/L、0.8 g/L、1.0 g/L的抑制物质量浓度下发酵，可分别产总溶剂15.2 g/L、14.4 g/L、12.7 g/L。

Screening of inhibitor-tolerant and butanol producing strain by ion beam implantation and continuous culturing domestication

The mutation method of ion beam implantation was employed to Clostridium beijerinckii NCIMB 8052 in this study. As a result, a mutant strain C. beijerinckii CN18 was screened. Comparing to the original strain, the buranol production increased from 9.9 g/L to 12.8 g/L, which improved 29.3%. Meanwhile, the total solvent production was 18.2 g/L, which was 35.8% higher than the original data of 13.4 g/L. Additionally, C. beijerinckii CN18 could maintain stable solvent production during 20 times serial passages, which showed excellent genetic stability. In the following, a mutant strain C. beijerinckii CN88 with high resistance of lignin-degraded products was obtained after continuous culturing domestication, which could grow well even under 1.0 g/L inhibitor. Under the inhibitor concentrations of 0.6 g/L, 0.8 g/L and 1.0 g/L, it could produce 15.2 g/L, 14.4 g/L and 12.7 g/L total solvents, respectively.