Abstract：
OBJECTIVE: Acinetobacter baumannii is a nosocomial pathogen known to be multidrug-resistant (MDR), especially to drugs of the carbapenem class. Several factors contribute to resistance, including efflux pumps, β-lactamases, alteration of target sites, and permeability defects. In addition, outer membrane proteins (OMPs), like porins are involved in the passage of antibiotics, and their alteration could lead to resistance development. This study aimed to explore the possible involvement of porins and OMPs in developing carbapenem resistance due to differential expression.
RESULTS: The antibiotic-susceptible and MDR isolates of A. baumannii were first studied for differences in their transcriptional levels of OMP expression and OMP profiles. The antibiotic-susceptible isolates were further treated with imipenem, and it was found that the omp genes were differentially expressed. Six of the nine genes studied were upregulated at 1 h of exposure to imipenem. Their expression gradually decreased with time, further confirmed by their OMP profile and two-dimensional gel electrophoresis.
CONCLUSIONS: This study could identify OMPs that were differentially expressed on exposure to imipenem. Hence, this study provides insights into the role of specific OMPs in antibiotic resistance in A. baumannii.
RESULTS: The antibiotic-susceptible and MDR isolates of A. baumannii were first studied for differences in their transcriptional levels of OMP expression and OMP profiles. The antibiotic-susceptible isolates were further treated with imipenem, and it was found that the omp genes were differentially expressed. Six of the nine genes studied were upregulated at 1 h of exposure to imipenem. Their expression gradually decreased with time, further confirmed by their OMP profile and two-dimensional gel electrophoresis.
CONCLUSIONS: This study could identify OMPs that were differentially expressed on exposure to imipenem. Hence, this study provides insights into the role of specific OMPs in antibiotic resistance in A. baumannii.
摘要：
目的：鲍氏不动杆菌是一种已知的多药耐药（MDR）的医院病原菌，尤其是碳青霉烯类药物。有几个因素有助于抵抗，包括外排泵,β-内酰胺酶,改变目标部位，和渗透性缺陷。此外,外膜蛋白（OMPs）如孔蛋白参与抗生素的通过，它们的改变可能导致抗性发展。本研究旨在探讨由于差异表达，孔蛋白和OMPs可能参与碳青霉烯耐药性的发展。
结果：首先研究了鲍曼不动杆菌的抗生素敏感和MDR分离株的OMP表达和OMP谱的转录水平差异。抗生素敏感的分离株进一步用亚胺培南治疗，结果发现omp基因差异表达。所研究的9个基因中的6个在暴露于亚胺培南1小时时上调。它们的表达随时间逐渐降低,进一步证实了他们的OMP图谱和二维凝胶电泳。
结论：本研究可以确定暴露于亚胺培南后差异表达的OMPs。因此，这项研究提供了特定OMPs在鲍曼不动杆菌抗生素耐药性中的作用的见解。
结果：首先研究了鲍曼不动杆菌的抗生素敏感和MDR分离株的OMP表达和OMP谱的转录水平差异。抗生素敏感的分离株进一步用亚胺培南治疗，结果发现omp基因差异表达。所研究的9个基因中的6个在暴露于亚胺培南1小时时上调。它们的表达随时间逐渐降低,进一步证实了他们的OMP图谱和二维凝胶电泳。
结论：本研究可以确定暴露于亚胺培南后差异表达的OMPs。因此，这项研究提供了特定OMPs在鲍曼不动杆菌抗生素耐药性中的作用的见解。
