摘要
目的研究耐碳青霉烯类鲍曼不动杆菌膜蛋白机制并了解其流行型别。方法收集仁济医院、瑞金医院和上海市第六人民医院鲍曼不动杆菌共85株,其中亚胺培南和美罗培南耐药菌49株,敏感菌36株。用细菌基因组回文结构重复序列-聚合酶链反应(REP-PCR)分析其流行型别,PCR扩增检测碳青霉烯类水解酶及金属酶,对阳性扩增菌株进行DNA测序分析,同时用超声波和超速离心法提取细菌的膜孔蛋白并用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)进行分析。结果49株耐亚胺培南和美罗培南鲍曼不动杆菌中,REP-PCR分析结果以A型为主,与敏感菌株存在很大差异;耐药菌株中oxa-51均为阳性,45株为oxa-23阳性;36株敏感菌株中检测到1株oxa-58阳性,29株为oxa-51阳性;金属酶(VIM和IMP-1/4型)均阴性;膜蛋白分析显示,在36株耐药株中38 000附近条带缺失,而在30株敏感株中有17株在相应位置处表达该条带。结论耐碳青霉烯类鲍曼不动杆菌主要以A型流行,产oxa-23水解酶和38 000附近膜孔蛋白条带缺失可能是其主要耐药机制。
Objective To investigate the outer membrane protein mechanism of carbapenemase resistance on Acinetobacter baumannii and its epidemic patterns.Methods 85 Acinetobacter baumannii strains,including 49 imipenem-resistant and meropenem-resistant strains and 36 sensitive strains,were collected from Renji hospital,Ruijin hospital and Shanghai sixth people′s hospital.The epidemic patterns were analyzed by repetitive extragenic palindromic-polymerase chain reaction（REP-PCR）and the carbapenemase and metalloenzymes were detected by PCR amplification.The outer membrane proteins were extracted by sonication and ultracentrifuge and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE） after the positive results were sequenced.Results Type A was the major pattern in total carbapenemase resistance bacteria,but the patterns were very different from sensitive ones.The PCR results indicated that 45 isolates were positive for oxa-23 and all oxa-51 were positive in carbapenemase resistance isolates.Among 36 sensitive strains,1 isolate was positive for oxa-58 and 29 isolates were positive for oxa-51.The metalloenzymes,VIM and IMP-1/4,were all negative.Around position 38 000,17 of 30 sensitive isolates were expressed this protein while no one was detected in 36 resistance ones.Conclusions Type A is the major epidemic pattern in carbapenemase resistance Acinetobacter baumannii.The production of oxa-23 carbapenemase and the loss of 38 000 outer membrane protein may be the major mechanism.
出处
《检验医学》
CAS
北大核心
2010年第4期304-308,共5页
Laboratory Medicine
关键词
鲍曼不动杆菌
碳青霉烯类
膜蛋白
耐药机制
Acinetobacter baumannii
Carbapenemase
Outer membrane protein
Resistance mechanism
