Articles of Significant Interest in This Issue

Abstract

The stress sigma factor SigB of the foodborne pathogen Listeria monocytogenes is critical for infectivity. Guerreiro et al. (e00330-22) demonstrate the frequent emergence of SigB loss-of-function mutations under laboratory conditions due to the growth advantage they confer. The high occurrence rate of these and other advantageous mutations in publicly available genomes suggests widespread selection of unwanted hitchhiker mutations in laboratories worldwide.