GoTriple

authors

Contributors

School of Earth Sciences [Bristol] ; University of Bristol [Bristol],

Collection des Cyanobactéries ; Institut Pasteur [Paris],

BES was supported by the Swiss National Fund and is currently a Marie Curie Intra European Fellow (330849). PCJD was supported by the Natural Environment Research Council (NE/G016623/1), Biotechnology and Biological Sciences Research Council (BB/J00538X/1), a Royal Society Wolfson Merit Award and a Leverhulme Trust Research Fellowship. Sequencing work was financed by the ‘Black Swan Fund’ of the University of Bristol Faculty of Science.,

We acknowledge with thanks the help of Alan McNally, Jane Coghill, Christy Waterfall, Al Tanner, Davide Pisani and Mario dos Reis. Particular thanks goes to Callum Wright for support with the Bluecrystal high computing machines. We thank the Institut Pasteur for funding of the Pasteur Culture collection of Cyanobacteria, as well as Thierry Laurent and Thérèse Coursin for cyanobacterial maintenance and genomic DNA. Additionally, we would like to thank two anonymous reviewers for helpful comments and interesting discussion points. We further thank the Palaeobiology group at the University of Bristol for thoughtful comments. BES would like to thank the Palaeontological Association and Crispin Little for the invitation to contribute to the symposium at the 58th Annual Meeting of the Association in Leeds.,

European Project: 330849,EC:FP7:PEOPLE,FP7-PEOPLE-2012-IEF,EVOXY(2014)

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Abstract

This article is corrected by:Errata: Cyanobacteria and the Great Oxidation Event: evidence from genes and fossils Volume 58, Issue 5, 935–936, Article first published online: 14 August 2015; International audience; Cyanobacteria are among the most ancient of evolutionary lineages, oxygenic photosynthesizers that may have originated before 3.0 Ga, as evidenced by free oxygen levels. Throughout the Precambrian, cyanobacteria were one of the most important drivers of biological innovations, strongly impacting early Earth's environments. At the end of the Archean Eon, they were responsible for the rapid oxygena-tion of Earth's atmosphere during an episode referred to as the Great Oxidation Event (GOE). However, little is known about the origin and diversity of early cyanobacterial taxa, due to: (1) the scarceness of Precambrian fossil deposits; (2) limited characteristics for the identification of taxa; and (3) the poor preservation of ancient microfossils. Previous studies based on 16S rRNA have suggested that the origin of multi-cellularity within cyanobacteria might have been associated with the GOE. However, single-gene analyses have limitations, particularly for deep branches. We reconstructed the evolutionary history of cyanobacteria using genome scale data and re-evaluated the Precambrian fossil record to get more precise calibrations for a relaxed clock analysis. For the phylogenomic reconstructions, we identified 756 conserved gene sequences in 65 cyanobacterial taxa, of which eight genomes have been sequenced in this study. Character state reconstructions based on maximum likelihood and Bayesian phylogenetic inference confirm previous findings, of an ancient multicellular cyanobacterial lineage ancestral to the majority of modern cyanobacteria. Relaxed clock analyses provide firm support for an origin of cyanobacteria in the Archean and a transition to multicellularity before the GOE. It is likely that multicellu-larity had a greater impact on cyanobacterial fitness and thus abundance, than previously assumed. Multicellularity, as a major evolutionary innovation, forming a novel unit for selection to act upon, may have served to overcome evolutionary constraints and enabled diversification of the variety of mor-photypes seen in cyanobacteria today.