Introductory paragraphCyanobacteria oxygenated Earth’s atmosphere during the Great Oxygenation Event (GOE) through oxygenic photosynthesis. Their high iron requirement was presumed met by high levels of Fe(II) in the anoxic Archean ocean. Here we show that most basal Cyanobacteria cannot synthesize the primary Fe(II) transporter, FeoB. Relaxed molecular clock analyses estimate the arrival of FeoB, as well as the Fe(III) transporters, cFTR1 and FutB, in the Cyanobacteria after the GOE. Furthermore Pseudanabaena sp. PCC7367, a basal marine, benthic strain grown under simulated Archean conditions, constitutively expressed cftr1, even after the addition of Fe(II). By utilizing gene expression studies under a simulated Archean atmosphere, as well as comparative genomics, phylogenetics and molecular clock analyses, this study identified a need to reappraise iron uptake in ancestral Cyanobacteria, as genetic profiling suggests that scavenging of siderophore bound Fe(III), rather than Fe(II), appears to have been the means of iron acquisition prior to the GOE.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.