摘要
目的:敲除毒死蜱降解菌Klebsiellasp.CPK菌中的relA基因,研究其对毒死蜱降解的影响。方法:采用同源重组技术敲除了Klebsiellasp.CPK菌中魔斑合成酶编码基因relA,通过PCR及RT-PCR扩增对其敲除进行了验证,分别采用分光光度法和气相色谱检测了该突变体对毒死蜱的耐受性和对毒死蜱的降解。结果:获得了一株relA基因敲除菌株△relA。在毒死蜱胁迫下,△relA菌株的耐受能力和对毒死蜱的降解能力均弱于野生型的CPK菌株。在初始降解的第一天,两者的降解速率相差最大,CPK菌株对毒死蜱的降解率高达50%以上,而△relA菌株对毒死蜱的降解率却低于15%。结论:relA基因的产物魔斑参与调控了Klebsiellasp.CPK菌在毒死蜱胁迫下的严谨反应,可能以此增强了该菌株对毒死蜱的耐受性并促进了它对毒死蜱的降解。
Objective：To Knock out the relA gene of Klebsiella sp.CPK and analyze its effects on biodegradation chlorpyrifos.Method： A Klebsiella sp.CPK △relA strain was obtained by homologous recombination and it was verified by PCR and RT-PCR amplification.Then the tolerance of the △relA strain to chlorpyrifos was detected by spectrophotometer assay.Degradation of chlorpyrifos by △relA strain was detected by gas chromatography.Result： A △relA strain was obtained.It was more sensitive to chlorpyrifos stress and the degradation rate of △relA strain to chlorpyrifos was significantly slower than that of CPK strain.The largest difference of the degradation rate between two strains appeared at the the initial day and 50% CP was degraded by CPK strain,while no more than 15% CP was degraded by △ relA strain.Conclusion：（p）ppGpp pools,the product of RelA,modulated the response of Klebsiella sp.CPK strain to chlorpyrifos stress,might enhance its tolerance to the toxicity of chlorpyrifos and promote the degradation of chlorpyrifos.
出处
《生物技术》
CAS
CSCD
北大核心
2010年第6期38-41,共4页
Biotechnology
基金
国家高科技研究发展计划"863"项目(2008AA10Z402
2006AA10Z401)
中国农业科学院基础研究基金项目(0042009001)资助
关键词
克雷伯氏菌
魔斑合成酶基因
毒死蜱
降解
Klebsiella sp
（p）ppGpp synthetase gene
chlorpyrifos
degradation
