CAJ | 학술논문

目的研究膜蛋白在耐碳青霉烯类抗生素鲍曼不动杆菌中的作用.方法从同一住院病人体内分别收集碳青霉烯类敏感和耐药的鲍曼不动杆菌各1株.经多序列位点测序分型(MIST)和细菌基因组外回文结构重复序列分型(REP-PCR)分析后,等电聚焦电泳检测其已知碳青霉烯类水解酶的表达,在此进行膜蛋白二维电泳和质谱鉴定分析,并最后应用PABN(Phe-Arg-β-naphthylamide)外排泵抑制剂检测其外排泵相关膜蛋白表达.结果 MIST和REP-PCR结果表明耐药株来源与敏感菌株属于同一型别;等电聚焦电泳在P17.6和P19.0处两株菌中检测到β-内酰胺酶,没有检测到任何已知的碳青霉烯类水解酶;耐约株和敏感株的差异膜蛋白组学鉴定出相对分子质量(M_r)为34×10~3外排泵膜蛋白和0prD与CarO膜孔蛋白,且后续的外排泵抑制剂试验表明,在PAβN存在的情况下,耐药株的亚胺培南最低抑菌浓度(MIC)由大于32 μg/ml下降到8 μg,/ml.结论本研究发现外排泵膜蛋白的过度表达伴随OprD和CarO膜孔蛋白的下调是临床分离耐碳青霉烯类抗生素鲍曼不动杆菌主要耐药机制.
목적 연구막단백재내탄청매희류항생소포만불동간균중적작용.방법 종동일주원병인체내분별수집탄청매희류민감화내약적포만불동간균각1주.경다서렬위점측서분형(MIST)화세균기인조외회문결구중복서렬분형(REP-PCR)분석후,등전취초전영검측기이지탄청매희류수해매적표체,재차진행막단백이유전영화질보감정분석,병최후응용PABN(Phe-Arg-β-naphthylamide)외배빙억제제검측기외배빙상관막단백표체.결과 MIST화REP-PCR결과표명내약주래원여민감균주속우동일형별;등전취초전영재P17.6화P19.0처량주균중검측도β-내선알매,몰유검측도임하이지적탄청매희류수해매;내약주화민감주적차이막단백조학감정출상대분자질량(M_r)위34×10~3외배빙막단백화0prD여CarO막공단백,차후속적외배빙억제제시험표명,재PAβN존재적정황하,내약주적아알배남최저억균농도(MIC)유대우32 μg/ml하강도8 μg,/ml.결론 본연구발현외배빙막단백적과도표체반수OprD화CarO막공단백적하조시림상분리내탄청매희류항생소포만불동간균주요내약궤제.
Objective To investigate the role of outer membrane protein in clinical isolated car-bapenem resistance Acinetobacter baumannii. Methods Carbapenem resistance and sensitive strains were collected from the same patient. After MIST and REP-PCR analysis, carbapenemases were detected by isoe-lectric focusing. Different expressed membrane proteins were identified by two-dimension electrophoresis and mass spectrometry analysis. We also used efflux pump inhibitor PAβN(Phe-Arg-β-naphthylamide) to con-firm the phenotype. Results Carbapenem resistance and sensitive strains were attributed to the same pat-tern. At positions of P17.6 and P19.0, two β-lactamases were expressed in two investigated strains, no cabapenemases were detected. Six differential expressed membrane proteins were identified, a 34 × 10~3 membrane protein that was confirmed by efflux pump inhibitor PAβN experiment (imiponem MIC decreased from far above 32 μg/ml to 8μ/ml) and OprD and CarO. Conclusion Up-regulation of exported protein accompanied with down-regulation of OprD and CarO other than carbaponemases are responsible for carbap-enem resistance in A. baumannii.