Bacteriophages as Antimicrobial Agents? Proteomic Insights on Three Novel Lytic Bacteriophages Infecting ESBL-Producing Escherichia coli

With the emergence of multiresistant bacteria, the use of bacteriophages is gaining renewed interest as potential antimicrobial agents. The aim of this study was to analyze the structure of three lytic bacteriophages infecting Escherichia coli (SD1, SD2, and SD3) using a gel-based proteomics approach and the cellular response of this bacterium to phage SD1 infection at the proteome level. The combination of the results of 1-DE and 2-DE followed by mass spectrometry led to the identification of 3, 14, and 9 structure proteins for SD1, SD2, and SD3 phages, respectively. Different protein profiles with common proteins were noticed. We also analyzed phage-induced effects by comparing samples from infected cells to those of noninfected cells. We verified important changes in E. coli proteins expression during phage SD1 infection, where there was an overexpression of proteins involved in stress response. Our results indicated that viral infection caused bacterial oxidative stress and bacterial cells response to stress was orchestrated by antioxidant defense mechanisms. This article makes an empirical scientific contribution toward the concept of bacteriophages as potential antimicrobial agents. With converging ecological threats in the 21st century, novel approaches to address the innovation gaps in antimicrobial development are more essential than ever. Further research on bacteriophages is called for in this broader context of planetary health and integrative biology.