鲍曼不动杆菌中CarO表达、序列突变与亚胺培南敏感性关系的研究

目的研究外膜蛋白CarO的表达、序列突变与鲍曼不动杆菌对亚胺培南敏感性的关系。方法收集鲍曼不动杆菌8株．E—test鉴定亚胺培南敏感性；用脉冲场凝胶电泳（PFGE）鉴定菌株同源性；PCR法检验CarO基因，并进行序列分析：RealtimePCR法检验CarOmRNA的表达；SDS电泳法比较CarO蛋白的表达。结果本实验发现4株耐药菌株CarO序列同源性高；所有菌株中均存在CarO基因，但亚胺培南敏感及耐药菌株基因序列相似性仅87％，敏感菌株与耐药菌株均有CarOmRNA基因表达，且两者表达水平差异无统计学意义；SDS电泳也发现其基因序列不同者CarO蛋白分子量不同。结论CarO基因序列改变可能与鲍曼不动杆菌对亚胺培南敏感性的变化有关。

The study of the relationship of CarO expression,gene mutation and Imipine sensitivity of Acinetobacter baumannii

Objective To study the relationship of CarO expression, gene mutation and Imipine sensitivity of Acinetobacter baumannii. Methods 8 strains of Acinetobacter baumannii were collected. Imipine MICs were determined by E-Test. The homology of the isolates was determined by PFGE. The CarO gene was amplified by polymerase chain reaction （PCR） and the PCR products were sequenced. The gene expression of CarO mRNA was carried out by Real-time PCR. Outer membrane protein was extracted and analyzed by SDS-PAGE. Results All isolates had the CarO gene and the CarO gene in 4 isolates had a high degree of homology. 87% of the isolates were sensitive to imipine and had similar gene sequences. All isolates expressed CarO mRNA, and the levels of gene expression were similar. The variation in the apparent molecular weight of the CarO protein was correlated with the variation of the CarO gene sequence. Conclusion The change of the Imipine sensitivity of Acinetobacter baumannii was correlated with the CarO gene mutation.