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bioRxiv · 10.64898/2026.10.06.756941

Conserved synteny reveals a saccharolytic lifestyle across Kiritimatiellia

Oliver, A.·Podell, S.·Allen, E. E.
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Abstract

Kiritimatiellia are a class of Verrucomicrobiota whose few cultured representatives are known for hosting large repertoires of carbohydrate-active enzymes and sulfatases. Many families of this class are restricted to metagenome-assembled genomes not yet discussed in literature, leaving their genome organization undescribed. Here, we survey 898 Kiritimatiellia genomes using similarity-colocalization networks (SCoNes), a data structure that captures conserved synteny among homologous genes across genomes. Using this approach, we investigate four metabolic adaptations to a glycan-rich environment: complex polysaccharide degradation, nitrogen cycling, hydrogenase activity, and natural product biosynthesis. Rather than unrelated functions, these capacities envelop a single anaerobic and saccharolytic strategy where sulfated glycan hydrolysis fuels fermentation, hydrogenases balance redox, and excess carbon supports nitrogen fixation.

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Oliver, A., Podell, S., Allen, E. E.. 2026-10-08. Conserved synteny reveals a saccharolytic lifestyle across Kiritimatiellia. https://doi.org/10.64898/2026.10.06.756941

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