Our results show that even the most conserved genes have significant variants in natural biomes. These could be indicative of novel taxonomic groups and divergent biologies at play in the global ocean.

We hope that these results can guide future targeted searches into microbial dark matter! 🕵️🔬

We then highlight intriguing oceanic variants in three gene families. One of these is the SMC family, which binds DNA by opening up its "hinge" domain.

Interestingly, we detected an abundant marine clade of hinge-less SMCs in Actinobacteria, hinting at marked functional novelty in this family! ⤵️

Our first observation was that div. variants of these old, conserved genes are... everywhere. Every oceanic location hosts some of these sequences - 20% of their entire seq. content on avg. Depth had some influence locally, but on a global scale, even shallow waters are rife with such variants! ⤵️

We present an iterative model to detect increasingly distant homologues in a target dataset.

Simulations show that our method can find distant variants missed by direct searches, without increased risk of false positives.

We then looked for div. variants of 53 core genes in marine microbiomes ⤵️