肠炎沙门菌iroB基因缺失株的构建及部分特性分析

Construction of iroB gene-knockout strain of Salmonella enterica and its characteristic analysis

为研究糖基转移酶IroB对沙门菌的重要作用,本研究利用λ-Red重组技术构建了肠炎沙门菌iroB基因缺失突变株c50336ΔiroB,通过应激试验、胞内存活试验和药物耐受试验检测缺失iroB基因后肠炎沙门菌生物特性的变化。结果显示,iroB基因缺失并未影响细菌的生长速度和生化特性,也不影响其对酸、碱和过氧化氢的抵抗能力,以及其在细胞内的存活能力,但使得细菌对热应激的敏感性增加,对蛋清抵抗能力下降,推测IroB参与沙门菌对铁的利用和对多溶菌酶的耐受;利用多粘菌素B进行最低抑菌浓度试验,结果显示其耐该药能力降低。本研究结果揭示IroB能够促进肠炎沙门菌的抗应激能力和耐药性,阐释了糖基转移酶IroB在沙门菌致病过程中的作用。

To investigate the roles of C-glycosyltransferase IroB of Salmonella enterica,the iroB gene-knockout strain of S.enterica was constructed byλ-Red recombination,and its contribution to pathogenic mechanism of S.enterica was analyzed by stress test,drug sensitive test and cell infection test.The data demonstrated that,the iroB-deficient mutant showed no difference in growth characteristics,biochemical characteristics,intracellular survival ability and acid,alkali and oxidative stress,compared with wild type strain.However,the mutant strain showed increased sensibility to heat stress and survival defection in albumen.The possible molecular mechanisms is that IroB contribute to the survival of S.enterica under iron-limited conditions and in lysozyme.The results revealed IroB contributed to the anti-stress ability and drug resistence and explored underlying the role of IroB on the pathogenidty of S.enterica.