SpoVG Is a Conserved RNA-Binding Protein That Regulates Listeria monocytogenes Lysozyme Resistance, Virulence, and Swarming Motility

Abstract

<i>spoVG</i> is widely conserved among bacteria; however, the function of this gene has remained unclear since its initial characterization in 1977. Mutation of <i>spoVG</i> impacts various phenotypes in Gram-positive bacteria, including methicillin resistance, capsule formation, and enzyme secretion in <i>Staphylococcus aureus</i> and also asymmetric cell division, hemolysin production, and sporulation in <i>Bacillus subtilis</i>. Here, we demonstrate that <i>spoVG</i> mutant strains of <i>Listeria monocytogenes</i> are hyper-lysozyme resistant, hypervirulent, nonmotile, and misregulate genes controlling carbon metabolism. Furthermore, we demonstrate that SpoVG is an RNA-binding protein. These findings suggest that SpoVG has a role in <i>L. monocytogenes</i>, and perhaps in other bacteria, as a global gene regulator. Posttranscriptional gene regulators help bacteria adapt to various environments and coordinate differing aspects of bacterial physiology. SpoVG may help the organism coordinate environmental growth and virulence to survive as a facultative pathogen.