高产雷帕霉素的游动放线菌菌种的选育

The Breeding of High-yielding Actinoplanes of Rapamycin

以游动放线菌(Actinoplanes)BCLP-016为出发菌株,采用常压室温等离子体(ARTP)诱变技术对其孢子进行处理,并将三个不同时间处理的孢子悬液混合。稀释涂布后,根据菌株菌落形态挑取部分单菌落进行初筛,经发酵复筛后,筛选得到了一株雷帕霉素高产菌株ARTP-039,其雷帕霉素的产量可达到369.39mg/L,较出发菌株BCLP-016的产量256.86 mg/L,提高了43.81%。以筛选出的ARTP-039高产菌为出发菌株,进行传统的紫外诱变,选取高、中、低三个致死率相对应的时间对其孢子悬液进行处理,并基于核糖体工程的理论选取了链霉素、庆大霉素、利福平、氯霉素和红霉素五种抗性物质,进行抗性初筛。发酵复筛后,最终筛选得到了一株雷帕霉素高产菌株St8+Gen6+Rif9+Chl3+Er4-015,该菌株同时具有五种抗性。该菌株的摇瓶实验结果表明,发酵7d后,其雷帕霉素的产量可达到589.79mg/L,较出发菌株BCLP-016的产量,提高了129.61%,且其遗传稳定性良好。

The Actinoplanes of BCLP-016 was selected as the original strain, and a mutagenesis of atmospherie and room temperature plasma （ARTP） was used to treat its spores, the spore suspension treated with three different time was mixed. After dilution coated, picking some single colonies according to the colony morphology of the strain for screening, after fermentation rescreening, a high-yielding strain of rapamycinARTP- 039 was screened out, its rapamyein production can reach 369.39mg/L, compared with the yield of the original strain BCLP-016 256.86 mg/L, increased by 43.81%. Choosing the high-yielding strain ARTP-039 as the starting strain, the traditional UV mutagenesis was conducted, three time that corresponding with fatality rate was selected to treat its spore suspension, based on the theory of the ribosome engineering, picking out five kinds of resistant material of streptomycin, gentamicin, rifampiein, chloramphenicol and erythromycin to conduct the resistanee screening. After fermentation rescreening, a high-yielding strain of Sts ＋ Gen6 ＋ Rif9 ＋ Chl3 ＋ Er4-015 was screened out, it has five kinds of resistance. The strain fermentation test showed that after 7 days of fermentation, the rapamycin output can reach 589.79mg/L, compared with the original strain BCLP-016 yield increased by 129.61% ,and its genetic stability is good.