Extreme marine environments, such as deep-sea cold seeps and hydrothermal vents, are characterized by high pressures, extreme temperatures, and steep chemical gradients—conditions similar to early Earth or periods of environmental upheaval. Despite these extreme physicochemical conditions, diverse microbial communities adapt and thrive in these environments, shaping local biogeochemical processes. Magnetotactic bacteria (MTB) are the only known magnetosensitive prokaryotes, capable of using the Earth's magnetic field for orientation and navigation to favored niches with optimal redox interfaces essential for their survival. This study investigates the diversity and abundance of MTB in deep-sea cold seeps and hydrothermal vents, revealing novel MTB genomes from previously unreported bacterial phyla, thereby broadening the known phylogeny of magnetotaxis. Through magnetosome biomineralization, MTB contribute significantly to iron cycling, and their versatile metabolisms may influence biogeochemical cycles within local environments.

Magnetotactic Bacteria,Cold Seeps,Hydrothermal Vents,Biogeochemical Cycles