Centro de Análises Proteômicas e Bioquímicas, Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília-DF, 70.790-160, Brazil.
Programa de Pós-Graduação em Patologia Molecular, Faculdade de Medicina, Universidade de Brasília, Brasília-DF, 70.910-900, Brazil.
Sci Rep. 2017 Jun 23;7(1):4197. doi: 10.1038/s41598-017-04181-y.
In recent years the antimicrobial peptides (AMPs) have been prospected and designed as new alternatives to conventional antibiotics. Indeed, AMPs have presented great potential toward pathogenic bacterial strains by means of complex mechanisms of action. However, reports have increasingly emerged regarding the mechanisms by which bacteria resist AMP administration. In this context, we performed a comparative proteomic study by using the total bacterial lysate of magainin I-susceptible and -resistant E. coli strains. After nanoUPLC-MS analyses we identified 742 proteins distributed among the experimental groups, and 25 proteins were differentially expressed in the resistant strains. Among them 10 proteins involved in bacterial resistance, homeostasis, nutrition and protein transport were upregulated, while 15 proteins related to bacterial surface modifications, genetic information and β-lactams binding-protein were downregulated. Moreover, 60 exclusive proteins were identified in the resistant strains, among which biofilm and cell wall formation and multidrug efflux pump proteins could be observed. Thus, differentially from previous studies that could only associate single proteins to AMP bacterial resistance, data here reported show that several metabolic pathways may be related to E. coli resistance to AMPs, revealing the crucial role of multiple "omics" studies in order to elucidate the global molecular mechanisms involved in this resistance.
近年来，抗菌肽 (AMPs) 被视为传统抗生素的替代品而备受关注和设计。事实上，抗菌肽通过复杂的作用机制对致病菌株表现出巨大的潜力。然而，关于细菌对抗菌肽给药的抵抗机制的报道越来越多。在这种情况下，我们通过使用对magainin I 敏感和耐药的大肠杆菌菌株的总细菌裂解物进行了比较蛋白质组学研究。经过 nanoUPLC-MS 分析，我们在实验组中鉴定出 742 种蛋白质，在耐药菌株中表达了 25 种差异表达的蛋白质。其中，涉及细菌耐药性、内稳态、营养和蛋白质转运的 10 种蛋白质上调，而与细菌表面修饰、遗传信息和β-内酰胺结合蛋白相关的 15 种蛋白质下调。此外，在耐药菌株中还鉴定出 60 种独特的蛋白质，其中可以观察到生物膜和细胞壁形成以及多药外排泵蛋白。因此，与之前只能将单个蛋白质与 AMP 细菌耐药性相关联的研究不同，这里报道的数据表明，几个代谢途径可能与大肠杆菌对抗 AMP 的耐药性有关，揭示了进行多种“组学”研究以阐明涉及这种耐药性的全局分子机制的关键作用。
