Fig. 1

Phylogenetic analysis of uncultured UBA5794 actinobacteria. (A) Prokaryotic community composition at the order level (relative abundance > 1%) of the enriched sample of deep-sea hydrothermal sediment N04, based on 16S full-length rRNA gene amplification. (B) The maximum-likelihood (ML) phylogenetic tree based on 16S rRNA genes of the 12 main OTUs obtained in this study and those from representative “Ca. Actinomarinales” MAGs. The tree was constructed with MEGA11. Three dominant OTUs (OTU2, 4, and 9) are shown in red font. (C) Genome-wide ML phylogenetic analysis of the class Acidimicrobiia based on the 120 bacterial concatenated marker proteins identified by GTDB-Tk. All the orders of Acidimicrobiia by the GTDB taxonomy are included in this phylogenomic tree, with outgroups of nearby actinobacterial classes (Actinomycetia, Coriabacteriia, and Thermoleophilia). The tree was constructed using IQ-tree (v2.1.2) with parameters: iqtree -m MFP -bb 1000 -bnni -nt AUTO, and the branches are collapsed into triangles at the order or class level