Surviving Bacterial Sibling Rivalry: Inducible and Reversible Phenotypic Switching in Paenibacillus dendritiformis

Author :Avraham Be'er, E.-L. Florin, Carolyn R. Fisher, Harry L. Swinney, and Shelley M. Payne
Editor :Jeff Miller, UCLA School of Medicine
Publication :mBio
Publisher :ASM
Volume :2
Number :3
Year :2011

Natural habitats vary in available nutrients and room for bacteria to grow, but successful colonization can lead to
overcrowding and stress. Here we show that competing sibling colonies of Paenibacillus dendritiformis bacteria survive overcrowding
by switching between two distinct vegetative phenotypes, motile rods and immotile cocci. Growing colonies of the rodshaped
bacteria produce a toxic protein, Slf, which kills cells of encroaching sibling colonies. However, sublethal concentrations
of Slf induce some of the rods to switch to Slf-resistant cocci, which have distinct metabolic and resistance profiles, including
resistance to cell wall antibiotics. Unlike dormant spores of P. dendritiformis, the cocci replicate. If cocci encounter conditions
that favor rods, they secrete a signaling molecule that induces a switch to rods. Thus, in contrast to persister cells, P. dendritiformis
bacteria adapt to changing environmental conditions by inducible and reversible phenotypic switching.