Bacterial arms race may shape gut microbiome

Researchers wanted to understand what forces drive the composition and ecology of microbes that live in people's guts. The human gut microbiome is critical to aspects of health and disease. The researchers found that several of the Bacteroides species that populate the gut have sizable gene-cluster defenses that neutralize toxins from competitor organisms. The clusters have features that suggest they are actively acquiring new immunity genes as new threats are encountered.