Fig. 6

The gene frequency and taxonomic composition of polar metagenome assembled genomes (MAGs) involved in DMS/DMSP cycling in polar oceans. a Frequency of DMS/DMSP cycling-related genes in 143 (out of 214) polar MAGs. MAGs are separated into four groups with MAGs in groups 1 to 3 carrying 1 to 3 types of DMS/DMSP cycling-related genes, MAGs in group 4 contains more than 3 types of DMS/DMSP cycling-related genes. The co-occurrence networks of protein-protein (b, d) and pathway-pathway (c, e) coexistence modes in DMS/DMSP cycling in MAGs obtained from polar oceans (b, c) compared to all microbial genomes in the IMG/M database (d, e). The cluster of each network was shown in its lower left corner. Each node in the networks indicates one protein (b, d) or one pathway (c, e) involved in DMS/DMSP cycling. The proteins in the same catabolic pathway (as indicated in Table 1) are marked using the same colour, and different pathways are distinguished using numbers 1–7. The size of nodes and the thickness of edges represent the frequencies of genes and MAGs carrying multiple genes involved in DMS/DMSP cycling, respectively.