Fig. 6: Characterization of auxiliary metabolic genes (AMGs) in the built environment (BE) viromes.

a A heatmap of the average abundance of each AMG in the BE habitats. The average abundance was calculated based on the average abundance of the viruses harboring the corresponding AMGs in each habitat. b A schematic that illustrates the insertion of genes by a virus disrupting the host genome. The region of genes in the host that was missing based on comparative genomic analysis with a closely related strain is highlighted by a gray dashed box. c A schematic that illustrates the insertion of two AMGs controlling a specific step of sulfate reduction by a virus into a host. The proviral region is highlighted by a gray dashed box, and the AMGs are highlighted by a red dashed box. The host genes (black dashed box) and pathways involved in sulfur metabolism are shown. d A schematic that illustrates the insertion of five AMGs encoding the entire preQ₀ biosynthesis pathway by a virus into a host. The AMGs are highlighted by a red dashed box.