title: The biogeography and phylogeny of unicellular cyanobacterial symbionts in sponges from Australia and the Mediterranean.
abstract: The distribution, host associations, and phylogenetic relationships of the unicellular cyanobacterial symbionts of selected marine sponges were investigated with direct 16s rDNA sequencing. The results indicate that the symbionts of the marine sponges Aplysina aerophoba, Ircinia variabilis, and Petrosia ficiformis from the Mediterranean, four Chondrilla species from Australia and the Mediterranean, and Haliclona sp. from Australia support a diversity of symbionts comprising at least four closely related species of Synechococcus. These include the symbionts presently described as Aphanocapsa feldmannii from P. ficiformis and Chondrilla nucula. A fifth symbiont from Cymbastela marshae in Australia is an undescribed symbiont of sponges, related to Oscillatoria rosea. One symbiont, Candidatus Synechococcus spongiarum, was found in diverse sponge genera in the Mediterranean Sea and the Indian, Pacific, and Southern oceans, whereas others were apparently more restricted in host association and distribution. These results are discussed in terms of the biodiversity and biogeographic distributions of cyanobacterial symbionts.
authors.affiliation: Discipline of Microbiology, School of Biomedical and Chemical Sciences, University of Western Australia, 6009, Crawley, Western Australia. kusher@cyllene.uwa.edu.au
authors.forename: K M
authors.initials: KM
authors.lastname: Usher
authors.forename: J
authors.initials: J
authors.lastname: Fromont
authors.forename: D C
authors.initials: DC
authors.lastname: Sutton
authors.forename: S
authors.initials: S
authors.lastname: Toze
mesh_terms: D000818:Animals; D001315:Australia; D001483:Base Sequence; D001499:Bayes Theorem; D000458:Cyanobacteria / Q000235:genetics*; D017931:DNA Primers; D004275:DNA, Ribosomal / Q000235:genetics; D003710:Demography; D004586:Electrophoresis; D005843:Geography; D016013:Likelihood Functions; D008522:Mediterranean Sea; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011161:Porifera / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013559:Symbiosis
chemical_list: D017931:DNA Primers; D004275:DNA, Ribosomal