title: Multi-locus sequence analysis, taxonomic resolution and biogeography of marine Synechococcus.
abstract: Conserved markers such as the 16S rRNA gene do not provide sufficient molecular resolution to identify spatially structured populations of marine Synechococcus, or 'ecotypes' adapted to distinct ecological niches. Multi-locus sequence analysis targeting seven 'core' genes was employed to taxonomically resolve Synechococcus isolates and correlate previous phylogenetic analyses encompassing a range of markers. Despite the recognized importance of lateral gene transfer in shaping the genomes of marine cyanobacteria, multi-locus sequence analysis of more than 120 isolates reflects a clonal population structure of major lineages and subgroups. A single core genome locus, petB, encoding the cytochrome b(6)  subunit of the cytochrome b(6) f complex, was selected to expand our understanding of the diversity and ecology of marine Synechococcus populations. Environmental petB sequences cloned from contrasting sites highlight numerous genetically and ecologically distinct clusters, some of which represent novel, environmentally abundant clades without cultured representatives. With a view to scaling ecological analyses, the short sequence, taxonomic resolution and accurate automated alignment of petB is ideally suited to high-throughput and high-resolution sequencing projects to explore links between the ecology, evolution and biology of marine Synechococcus.
authors.affiliation: School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, UK.
authors.forename: Sophie
authors.initials: S
authors.lastname: Mazard
authors.forename: Martin
authors.initials: M
authors.lastname: Ostrowski
authors.forename: Frédéric
authors.initials: F
authors.lastname: Partensky
authors.forename: David J
authors.initials: DJ
authors.lastname: Scanlan
mesh_terms: D059001:Aquatic Organisms; D001483:Base Sequence; D005075:Biological Evolution; D000458:Cyanobacteria / Q000145:classification / Q000235:genetics; D060146:Ecotype; D022761:Gene Transfer, Horizontal; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology; D017422:Sequence Analysis, DNA; D046940:Synechococcus / Q000145:classification / Q000235:genetics*; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S