Codjoe Francis S, Kotey Fleischer C N, Donkor Eric S
Department of Medical Laboratory Sciences, School of Biomedical & Allied Health Sciences, College of Health Sciences, University of Ghana, Accra, Ghana.
Biomolecular Science Research Centre, Sheffield Hallam University, Sheffield, England, UK.
BMC Res Notes. 2025 Feb 1;18(1):49. doi: 10.1186/s13104-024-07070-6.
Carbapenem resistance is a major global health threat, but insights on its molecular determinants are scanty in sub-Saharan Africa, the predominant global antimicrobial resistance hotspot. This study aimed to profile outer membrane proteins (OMPs) of 111 carbapenem-resistant Gram-negative bacteria recovered from a broad spectrum of clinical specimens from Ghana.
The OMPs of Pseudomonas aeruginosa produced decreased amounts of OprD or the porin was completely lost, except in 5.9% (n = 3) of the isolates which had high-level porins. For Acinetobacter baumannii, 96.8% (n = 30) expressed loss of OprF. One carbapenemase non-PCR-positive isolate with high-level porin expression was observed. In A. baumannii, the major and significant band on SDS-PAGE was ~ 35 kDa. There were substantial numbers of unrelated porin expression among the isolates. Particularly, OmpC/F or OmpK35/37 expression was deficient. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis for Escherichia coli, Klebsiella aerogenes, Klebsiella pneumoniae, and other Enterobacterales had OmpC and OmpF absent or markedly reduced compared to the control strains. Overall, porin loss was a major mechanism underlying carbapenem resistance among the isolates, suggesting that in carbapenem-resistant organisms that seem to lack known carbapenem resistance genes, porin loss may be the underlying carbapenem resistance mechanism.
碳青霉烯耐药是一项重大的全球健康威胁，但在撒哈拉以南非洲这一全球主要的抗菌药物耐药热点地区，对其分子决定因素的了解却很少。本研究旨在分析从加纳广泛的临床标本中分离出的111株耐碳青霉烯革兰氏阴性菌的外膜蛋白（OMP）。
铜绿假单胞菌的OMP中，除5.9%（n = 3）的分离株具有高水平孔蛋白外，OprD的产生量减少或孔蛋白完全缺失。对于鲍曼不动杆菌，96.8%（n = 30）表现出OprF缺失。观察到1株具有高水平孔蛋白表达的非碳青霉烯酶PCR阳性分离株。在鲍曼不动杆菌中，SDS-PAGE上的主要且显著条带约为35 kDa。分离株中存在大量不相关的孔蛋白表达。特别是，OmpC/F或OmpK35/37表达不足。与对照菌株相比，大肠杆菌、产气克雷伯菌、肺炎克雷伯菌和其他肠杆菌科细菌的十二烷基硫酸钠聚丙烯酰胺凝胶电泳（SDS-PAGE）分析显示OmpC和OmpF缺失或明显减少。总体而言，孔蛋白缺失是分离株中碳青霉烯耐药的主要机制，这表明在似乎缺乏已知碳青霉烯耐药基因的耐碳青霉烯生物体中，孔蛋白缺失可能是潜在的碳青霉烯耐药机制。
