Members of the Candidate Division OP10 are spread in a variety of environments

Our planet holds a huge bacterial diversity. Most of these bacteria have only been detected by their 16S rRNA gene sequences remaining to be cultured. Many are classified within Candidate Divisions. One them is the Candidate Division OP10. Analysis of environmental 16S rRNA gene sequences available in public repositories revealed the existence of numerous sequences clustering within the Candidate Division OP10 but currently unclassified or assigned to other bacterial phyla. Newly proposed 16S rRNA sequences multiply several fold the reported sequences for the Candidate Division OP10. This study showed that the Candidate Division OP10 is a diverse and broadly distributed bacterial phylum and represents a stable microbial component in different natural environments.