Fig. 3: Genetic isolation of SLM’s SAGs.

a A phylogenomic tree reconstructed using the concatenated GTDB protein sequence alignment that represents 122 SLM SAGs and 81 GTDB species representative genomes belonging to the family Gallionellaceae. The tree was rooted by an outgroup affiliated with the family SG8-39 of the order Burkholderiales. The 107 out of 108 SLM SAGs belonging to the genus Nitrotoga are cohesively clustered (see a circle in pink). The Shimodaira-Hasegawa support values for node confidence are presented next to the branches. b A histogram representing genomic average nucleotide identity (ANI) between SAGs and their closest GTDB genomes. The dotted vertical line at 95% sequence identity separates known and unknown bacterial species. When less than 10% of the SAG sequence aligned with any GTDB genomes, the SAG was considered a’No match‘. The ANI values for the 1374 SLM SAGs in orange and for 64 SAGs isolated from seawater beneath Ross Ice Shelf (RIS) in blue. c Histograms represent sequence similarity between query proteins and BLAST top hits of the NCBI NR database. The query proteins were derived from 537,441 and 45,895 orthologs that were clustered from the 1374 SLM SAGs (distribution in orange) and from the 64 RIS SAGs (distribution in blue), respectively. Two overlapped vertical bars on left represent the number of orthologs without significant BLAST hits under the E-value threshold 10. Source data are provided as a Source Data file.