Genomic insights into a versatile deep-sea methanotroph constituting the rare biosphere of a Brazilian carbonate mound complex

Microbial communities in deep-sea sediments play crucial roles in global biogeochemical cycles, yet they remain poorly characterized due to the challenges of sampling and culturing under extreme conditions. This study provides a comprehensive overview of microbial diversity and functional potential in carbonate-rich deep-sea sediments, with an emphasis on methane-oxidizing bacteria. By combining high-throughput metagenomics and comparative genomics, we reconstructed high-quality genomes from previously uncharacterized microbial consortia, including novel members of the genus <i>Methylotuvimicrobium</i>. Our findings shed light on the ecological strategies of methanotrophs in oxygen-limited environments and expand the genomic representation of key players in carbon cycling.