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Bacterial symbiont subpopulations have different roles in a deep-sea symbiosis.

ABSTRACT: The hydrothermal vent tubeworm Riftia pachyptila hosts a single 16S rRNA phylotype of intracellular sulfur-oxidizing symbionts, which vary considerably in cell morphology and exhibit a remarkable degree of physiological diversity and redundancy, even in the same host. To elucidate whether multiple metabolic routes are employed in the same cells or rather in distinct symbiont subpopulations, we enriched symbionts according to cell size by density gradient centrifugation. Metaproteomic analysis, microscopy, and flow cytometry strongly suggest that Riftia symbiont cells of different sizes represent metabolically dissimilar stages of a physiological differentiation process: While small symbionts actively divide and may establish cellular symbiont-host interaction, large symbionts apparently do not divide, but still replicate DNA, leading to DNA endoreduplication. Moreover, in large symbionts, carbon fixation and biomass production seem to be metabolic priorities. We propose that this division of labor between smaller and larger symbionts benefits the productivity of the symbiosis as a whole.

SUBMITTER: Hinzke T

PROVIDER: S-EPMC7787665 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Bacterial symbiont subpopulations have different roles in a deep-sea symbiosis.

Hinzke Tjorven T Kleiner Manuel M Meister Mareike M Schlüter Rabea R Hentschker Christian C Pané-Farré Jan J Hildebrandt Petra P Felbeck Horst H Sievert Stefan M SM Bonn Florian F Völker Uwe U Becher Dörte D Schweder Thomas T Markert Stephanie S

eLife 20210106

The hydrothermal vent tubeworm <i>Riftia pachyptila</i> hosts a single 16S rRNA phylotype of intracellular sulfur-oxidizing symbionts, which vary considerably in cell morphology and exhibit a remarkable degree of physiological diversity and redundancy, even in the same host. To elucidate whether multiple metabolic routes are employed in the same cells or rather in distinct symbiont subpopulations, we enriched symbionts according to cell size by density gradient centrifugation. Metaproteomic anal ...[more]

PMID: 33404502

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Dataset Information

Bacterial symbiont subpopulations have different roles in a deep-sea symbiosis.

Publications

Bacterial symbiont subpopulations have different roles in a deep-sea symbiosis.

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