Fig. 6

Prevalence of the genes associated with folate cofactor metabolism in the CPR superphylum. The maximum-likelihood phylogenomic tree of CPR from this study (n = 12) and the GTDB database (R220, n = 4581) was constructed based on 120 concatenated bacterial marker genes. Each class of CPR was represented by distinct colors in the inner circle. The phylogenomic groups comprising the MAGs affiliated with orders Paceibacterales, UBA6257, and UBA9973 in the present study were filled with yellow, purple, and blue backgrounds, respectively. From the outermost to the inner circles, the detection of folD, glyA, folA, and the taxonomic affiliation of the CPR bacteria was represented with different colors. The pathways for folate metabolism were illustrated in the bottom right with a green background, showing the proportion of CPR genomes carrying the genes involved in the metabolism of crucial folate cofactors