The bacterial tree of life has recently undergone significant expansion, chiefly from candidate phyla retrieved through genome-resolved metagenomics. Bypassing the need for genome availability, we present a snapshot of bacterial phylogenetic diversity based on the recovery of high-quality SSU rRNA gene sequences extracted from nearly 7000 metagenomes and all available reference genomes. We illuminate taxonomic richness within established bacterial phyla together with environmental distribution patterns, providing a revised framework for future phylogeny-driven sequencing efforts.
Keywords: Bacteria; Bacterial diversity; Candidate Phyla Radiation (CPR); Metagenomics; Microbial dark matter (MDM); Novel bacterial lineages; Small subunit (SSU) rRNA; Tree of life.