Takah. & Nozaki sp. nov.) based on differences in cell shape and surface ornamentations of the vegetative cells under the field-emission scanning electron microscope. Molecular phylogenetic analyses
of P700 chl a apoprotein A2 (psaB) genes and internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (rDNA), as well as a comparison of secondary structures of nuclear rDNA ITS-2 and genetic distances of psaB genes, supported the delineation of five morphological species of Cyanophora. “
“The family Microchaetaceae is a large group of heterocytous cyanobacteria, whose members bear typical morphological features of uniseriate heteropolar filaments never terminated by thin hairs and with simple false branching. However, phylogenetic analyses of the gene for 16S rRNA showed that members of this traditionally Selleck Saracatinib morphologically delimited family form several distant groups and therefore the current concept is hereafter indefensible. In this study, we provide
reassessment of the status of the family Microchaetaceae based on morphology, ecology, biogeography, and phylogeny of 16S rRNA gene. Thorough examination of strains of the nominate genus Microchaete revealed their affiliation to two groups, Nostocaceae and Rivulariaceae, and their distant position to other traditional members of Microchaetaceae such as Tolypothrix, Hassallia, and Coleodesmium. To reflect the phylogenetic relationships and to accommodate members of the traditional family Microchaetaceae that are clearly not Ipatasertib cost related to any of the Microchaete representatives, we propose establishment of two new families, Tolypothrichaceae and Godleyaceae. Based on both molecular and morphological evidence, we also provide a description of three new species of the genus Fortiea. “
“Three populations of the freshwater filamentous cyanobacterium Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck Monoiodotyrosine have been putatively identified from north-eastern Australia and found to produce the potent cyanotoxin cylindrospermopsin (CYN) and its
analog deoxy-cylindrospermopsin (deoxy-CYN). We investigated the phylogeny and toxicology of strains and mats isolated from two of these populations using a combination of molecular and morphological techniques. Morphologically the strains corresponded to the type description, however, the frequency of false-branching was low, and variable over time. Strains and mat samples from both sites were positive for the cyrF and cyrJ genes associated with CYN biosynthesis. Phylogenetic analysis of these genes from Australian L. wollei sequences and comparable cyanobacterial sequences revealed that the genes in L. wollei were more closely related to homologous genes in Oscillatoria sp. PCC 6506 than to homologs in Nostocalean CYN-producers. These data suggest a common evolutionary origin of CYN biosynthesis in L. wollei and Oscillatoria. In both the 16S rRNA and nifH phylogenies, the Australian L. wollei strains formed well-supported clades with United States L.