title: On the origins of oxygenic photosynthesis and aerobic respiration in Cyanobacteria.
abstract: The origin of oxygenic photosynthesis in Cyanobacteria led to the rise of oxygen on Earth ~2.3 billion years ago, profoundly altering the course of evolution by facilitating the development of aerobic respiration and complex multicellular life. Here we report the genomes of 41 uncultured organisms related to the photosynthetic Cyanobacteria (classOxyphotobacteria), including members of the classMelainabacteriaand a new class of Cyanobacteria (classSericytochromatia) that is basal to theMelainabacteriaandOxyphotobacteriaAll members of theMelainabacteriaandSericytochromatialack photosynthetic machinery, indicating that phototrophy was not an ancestral feature of the Cyanobacteria and thatOxyphotobacteriaacquired the genes for photosynthesis relatively late in cyanobacterial evolution. We show that all three classes independently acquired aerobic respiratory complexes, supporting the hypothesis that aerobic respiration evolved after oxygenic photosynthesis.
authors.affiliation: Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia.
authors.forename: Rochelle M
authors.identifier: 0000-0002-8927-2066
authors.initials: RM
authors.lastname: Soo
authors.affiliation: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.
authors.forename: James
authors.identifier: 0000-0001-7193-0553
authors.initials: J
authors.lastname: Hemp
authors.affiliation: Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia.
authors.forename: Donovan H
authors.initials: DH
authors.lastname: Parks
authors.affiliation: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA. p.hugenholtz@uq.edu.au wfischer@caltech.edu.
authors.forename: Woodward W
authors.identifier: 0000-0002-8836-3054
authors.initials: WW
authors.lastname: Fischer
authors.affiliation: Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia. p.hugenholtz@uq.edu.au wfischer@caltech.edu.
authors.forename: Philip
authors.identifier: 0000-0001-5386-7925
authors.initials: P
authors.lastname: Hugenholtz
mesh_terms: D000332:Aerobiosis; D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D005075:Biological Evolution; D000458:Cyanobacteria / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D014450:Electron Transport Complex III / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism*; D016680:Genome, Bacterial; D010100:Oxygen / Q000378:metabolism*; D010788:Photosynthesis / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny
chemical_list: D001426:Bacterial Proteins; D003576:Electron Transport Complex IV; D014450:Electron Transport Complex III; D010100:Oxygen