a Department of Medical Microbiology, Faculty of Medicine , University of Malaya , Kuala Lumpur , Malaysia.
b Department of Life Sciences, School of Pharmacy , International Medical University , Bukit Jalil , Kuala Lumpur , Malaysia.
Pathog Glob Health. 2018 Oct;112(7):378-386. doi: 10.1080/20477724.2018.1538281. Epub 2018 Oct 31.
The increasing prevalence of antibiotic resistant pathogens poses a serious threat to global health. However, less emphasis has been placed to co-relate the gene expression and metabolism of antibiotic resistant pathogens. This study aims to elucidate gene expression and variations in metabolism of multidrug resistant Klebsiella pneumoniae after exposure to antibiotics. Phenotypic responses of three genotypically distinct carbapenem resistant Klebsiella pneumoniae (CRKP) strains untreated and treated with sub-lethal concentrations of imipenem were investigated via phenotype microarrays (PM). The gene expression and metabolism of the strain harboring bla before and after exposure to sub-lethal concentration of imipenem were further investigated by RNA-sequencing (RNA-Seq) and H NMR spectroscopy respectively. Most genes related to cell division, central carbon metabolism and nucleotide metabolism were downregulated after imipenem treatment. Similarly, H NMR spectra obtained from treated CRKP showed decrease in levels of bacterial end products (acetate, pyruvate, succinate, formate) and metabolites involved in nucleotide metabolism (uracil, xanthine, hypoxanthine) but elevated levels of glycerophosphocholine. The presence of anserine was also observed for the treated CRKP while FAPγ-adenine and methyladenine were only present in untreated bacterial cells. As a conclusion, the studied CRKP strain exhibited decrease in central carbon metabolism, cell division and nucleotide metabolism after exposure to sub-lethal concentrations of imipenem. The understanding of the complex biological system of this multidrug resistant bacterium may help in the development of novel strategies and potential targets for the management of the infections.
抗生素耐药病原体的患病率不断上升，对全球健康构成了严重威胁。然而，人们对抗生素耐药病原体的基因表达和代谢之间的关系关注较少。本研究旨在阐明耐多药肺炎克雷伯菌（Klebsiella pneumoniae）暴露于抗生素后基因表达和代谢的变化。通过表型微阵列（phenotype microarrays，PM）研究了未经处理和用亚致死浓度亚胺培南处理的 3 种基因型不同的耐碳青霉烯类肺炎克雷伯菌（carbapenem resistant Klebsiella pneumoniae，CRKP）菌株的表型反应。用 RNA 测序（RNA-sequencing，RNA-Seq）和 H NMR 光谱法进一步研究了携带 bla 的菌株在暴露于亚致死浓度亚胺培南前后的基因表达和代谢。亚胺培南处理后，大多数与细胞分裂、中心碳代谢和核苷酸代谢相关的基因下调。同样，从处理过的 CRKP 获得的 H NMR 光谱显示，细菌终产物（乙酸盐、丙酮酸、琥珀酸盐、甲酸盐）和参与核苷酸代谢的代谢物（尿嘧啶、黄嘌呤、次黄嘌呤）的水平降低，但甘油磷酸胆碱的水平升高。处理过的 CRKP 中也存在天冬氨酸，而 FAPγ-腺嘌呤和甲基腺嘌呤仅存在于未经处理的细菌细胞中。总之，研究的 CRKP 菌株在暴露于亚致死浓度的亚胺培南后，表现出中心碳代谢、细胞分裂和核苷酸代谢减少。对这种多药耐药细菌复杂的生物学系统的了解可能有助于开发新的策略和潜在的管理感染的靶点。
