The under-recognized dominance of Verrucomicrobia in soil bacterial communities

► A total of 181 soils from Antarctica, Europe, and the Americas were analyzed via pyrosequencing. ► Verrucomicrobia was found to be a dominant phylum in soil, averaging 23% of bacterial 16S rRNA gene sequences. ► Relative abundance of Verrucomicrobia was highest in grasslands and some subsurface soils, where >50% of bacterial 16S rRNA gene sequences were verrucomicrobial. ► Abundance of Verrucomicrobia has been underestimated, probably due to primer bias. ► Class Spartobacteria was dominant within phylum Verrucomicrobia.