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Updated: May 16, 2026

Production and Visualization of Bacterial Spheroplasts and Protoplasts to Characterize Antimicrobial Peptide Localization
Published on: August 11, 2018
The role of bacterial membrane proteins in the internalization of microcin MccJ25 and MccB17
Indran Mathavan1, Konstantinos Beis
1Division of Molecular Biosciences, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK.
Abstract:
Microcins are gene-encoded antibacterial peptides of low molecular mass (<10 kDa), produced by Enterobactericeae. They are produced and secreted under conditions of limited essential nutrients and are active against related species. Bacterial strains under starvation conditions can produce and release microcins that can kill microcin-sensitive cells and therefore have more nutrients for survival. The outer-membrane protein OmpF and FhuA TonB-dependent pathways facilitate the internalization of the MccB17 and MccJ25 microcins into the target cell respectively. The inner-membrane protein SbmA transports the microcins through the inner membrane to the cytoplasmic face. Inside the cell, MccB17 targets DNA gyrase, whereas MccJ25 inhibits the bacterial RNA polymerase.
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