通过测定大肠杆菌K12 (Escherichia coli K12)菌悬液的OD260的变化, 研究了多粘类芽孢杆菌(Paenibacillus polymyxa)Cp-S316抗细菌活性物质对其细胞膜完整性的影响, 结果表明Cp-S316抗细菌活性物质可损伤大肠杆菌K12的细胞膜, 从而引起胞内RNA、DNA等大分子物质的泄漏。为获得抗细菌活性物质高产菌株, 以Cp-S316为出发菌株, 通过紫外诱变以及对自身产生的抗细菌活性物质的抗性筛选法进行预筛、摇瓶初筛和复筛, 获得突变株多粘类芽孢杆菌A17, 其发酵效价比出发菌株Cp-S316提高91%, 该突变株的高产遗传性状稳定。
The effect of antibacterial active substances from Paenibacillus polymyxa Cp-S316 on the integrity of Escherichia coli K12 membrane was studied by determining the variation of OD260 values of bacterial suspensions. The results showed that the antibacterial substances could damage the Escherichia coli K12 membrane which leaded to the leakage of RNA, DNA and other cytoplasmic macromolecules. As an original strain, Paenibacillus polymyxa Cp-S316 was treated by ultraviolet mutagenesis. The mutated strain of A17 was obtained by prescreening of antibacterial active substances, screening and re-screening of shake flask culture. Compared with Cp-S316, the yield of antibacterial substances obtained from mutant A17 was increased by 91%. The subculture experiments indicated that the hereditary characteristic of high productivity of Paenibacillus polymyxa A17 was stable.