Deep-branching magnetotactic bacteria form intracellular carbonates enriched in trace metals.

ABSTRACT: Microbial biomineralization is a fundamental driver of global biogeochemical cycles, yet the ability of prokaryotes to form intracellular carbonates remains rarely documented. Here, we report three ecotypes of magnetotactic bacteria (MTB) affiliated with the Pseudomonadota and the deep-branching Nitrospirota phyla that concurrently synthesize magnetite magnetosomes and intracellular calcium carbonate inclusions enriched in Ba, Mg, and Ni. These carbonate granules are typically spherical and contrast with the highly ordered morphology of magnetite crystals. Comparative genomic analyses reveal that these MTB encode multiple metal-permease systems (e.g., GDT1, CorA, ZnuA2), which suggests both a capacity for selective uptake of divalent cations from their environment and a proce

SUBMITTER: Liu P 

PROVIDER: S-EPMC12710302 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature