comparative proteomics of inner membrane fraction from carbapenem-resistant acinetobacter baumannii with a reference strain内膜分数的比较蛋白质组学从特拉鲍曼不动杆菌与应变的引用.pdf

Comparative Proteomics of Inner Membrane Fraction from Carbapenem-Resistant Acinetobacter baumannii with a Reference Strain 1 1 2 1 Vishvanath Tiwari , Jitendraa Vashistt , Arti Kapil , Rajeswari R. Moganty * 1 Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India, 2 Department of Microbiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India Abstract Acinetobacter baumannii has been identified by the Infectious Diseases Society of America as one of the six pathogens that cause majority of hospital infections. Increased resistance of A. baumannii even to the latest generation of b-lactams like carbapenem is an immediate threat to mankind. As inner-membrane fraction plays a significant role in survival of A. baumannii, we investigated the inner-membrane fraction proteome of carbapenem-resistant strain of A. baumannii using Differential In-Gel Electrophoresis (DIGE) followed by DeCyder, Progenesis and LC-MS/MS analysis. We identified 19 over- expressed and 4 down-regulated proteins (fold change.2, p ,0.05) in resistant strain as compared to reference strain. Some of the upregulated proteins in resistant strain and their association with carbapenem resistance in A. baumannii are: i) b- lactamases, AmpC and OXA-51: cleave and inactivate carbapenem ii) metabolic enzymes, ATP synthase, malate dehydrogenase and 2-oxoglutarate dehydrogenase: help in increased energy production for the survival and iii) elongation factor Tu and ribosomal proteins: help in the overall protein production. Further, entry of carbapenem perhaps is limited by controlled production of OmpW and low levels of surface antigen help to evade host defence mecha