TWiM reveals a study showing that positive interactions among bacteria are far more common than previously thought, and how acquisition of a single gene enabled Yersinia pestis to expand the range of mammalian hosts that sustain flea-borne plague.

Michael and Vincent present Spotlights, brief reviews of classic papers in the Journal of Bacteriology, and explain how a single bacterial species can reverse autism-like social deficits in the offspring of obese mice.