Chlamydial contribution to anaerobic metabolism during eukaryotic evolution

Abstract

The origin of eukaryotes is a major open question in evolutionary biology. Multiple hypotheses posit that eukaryotes likely evolved from a syntrophic relationship between an archaeon and an alphaproteobacterium based on H-2 exchange. However, there are no strong indications that modern eukaryotic H-2 metabolism originated from archaea or alphaproteobacteria. Here, we present evidence for the origin of H-2 metabolism genes in eukaryotes from an ancestor of the Anoxychlamydiales-a group of anaerobic chlamydiae, newly described here, from marine sediments. Among Chlamydiae, these bacteria uniquely encode genes for H-2 metabolism and other anaerobiosis-associated pathways. Phylogenetic analyses of several components of H-2 metabolism reveal that Anoxychlamydiales homologs are the closest relatives to eukaryotic sequences. We propose that an ancestor of the Anoxychlamydiales contributed these key genes during the evolution of eukaryotes, supporting a mosaic evolutionary origin of eukaryotic metabolism.

Published in

Science Advances
2020, Volume: 6, number: 35, article number: eabb7258Publisher: AMER ASSOC ADVANCEMENT SCIENCE

SLU Authors

• Tamarit Chuliá, Daniel

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    
  • Uppsala University
  • Wageningen University and Research

UKÄ Subject classification

Evolutionary Biology


Publication identifier

DOI: https://doi.org/10.1126/sciadv.abb7258

Permanent link to this page (URI)

https://res.slu.se/id/publ/107812