The Mosigvirus AV110 Elongasome-Modulating Peptide (Emp) inhibits Escherichia coli growth by targeting Mre-dependent peptidoglycan synthesis

Extended-spectrum {beta}-lactamase and AmpC-producing Escherichia coli (ESBL/AmpC E. coli) are increasingly recognized as public health threats due to their resistance to commonly used antibiotics. With limited treatment options available, new antibacterials and antibacterial targets can be explored by studying early-expressed phage proteins involved in host reprogramming, as these proteins interact with and disrupt essential bacterial processes. A systematic screening of 45 early-expressed proteins with unknown function of Mosigvirus AV110 identified six proteins that inhibit the growth of ESBL/AmpC E. coli, suggesting a role in host reprogramming. In-depth analysis of Gp94, termed Elongasome-Modulating Peptide (Emp), demonstrated that it alters cell morphology and the localization of peptidoglycan synthesis. This effect could be partially complemented by MreB and MreD. Since Emp interacts directly with MreB, MreC, and MreD, we propose that Emp perturbs elongasome-associated peptidoglycan synthesis, thus providing a scaffold for developing new antibacterials against ESBL/AmpC-producing E. coli.