Sulfur-Oxidizing Symbionts without Canonical Genes for Autotrophic CO₂ Fixation.

ABSTRACT: Since the discovery of symbioses between sulfur-oxidizing (thiotrophic) bacteria and invertebrates at hydrothermal vents over 40 years ago, it has been assumed that autotrophic fixation of CO₂ by the symbionts drives these nutritional associations. In this study, we investigated "Candidatus Kentron," the clade of symbionts hosted by Kentrophoros, a diverse genus of ciliates which are found in marine coastal sediments around the world. Despite being the main food source for their hosts, Kentron bacteria lack the key canonical genes for any of the known pathways for autotrophic carbon fixation and have a carbon stable isotope fingerprint that is unlike other thiotrophic symbionts from similar habitats. Our genomic and transcriptomic analyses instead found metabolic f

SUBMITTER: Seah BKB 

PROVIDER: S-EPMC6593406 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature