Life Sciences Commons^™

Two New Oculatella (Oculatellaceae, Cyanobacteria) Species In Soil Crusts From Tropical Semi–Arid Uplands Of México, Itzel Becerra–Absalón, Jeffrey R. Johansen, Karina Osorio–Santos, Gustavo Montejavo

2020 Faculty Bibliography

Two isolates of Oculatella from biological soil crusts in the arid and semi–arid tropical upland region of México were characterized using a polyphasic approach which included morphology, ecology, 16S rRNA and 16S–23S ITS phylogenetic analysis, percent identity of 16S rRNA gene sequence, percent dissimilarity of 16S–23S ITS sequence, and secondary structure of conserved ITS domains. The two species shared the generic synapomorphy of a reddish granule at the tip of mature apical cells, and possessed a single ribosomal

operon with both tRNA genes (tRNAIle and tRNAAla) based upon our analysis and the analysis of the other spe- cies in the …

Phylogeny And Taxonomy Of Synechococcus–Like Cyanobacteria, Jiri Komarek, Jeffrey R. Johansen, Jan Smarda, Otakar Strunecký

2020 Faculty Bibliography

Unicellular cyanobacteria constitute a substantial, ecologically important part of freshwater and marine microflora. Solitary, elongated cyanobacterial cells without apparent slime envelopes and dividing in a single plane perpendicular to the longitudinal axis were traditionally classified into the genus Synechococcus. The type species originates from a freshwater benthic habitat while a number of other Synechococcus–like species were described from diverse environments. Morphologically similar, unicellular populations of “Synechococcus” belong to the most abundant oxygen evolving prokaryotes inhabiting freshwater and oceanic picoplanktic communities. Other species from extreme thermal habitats were described from temperatures over 70 °C. Recent molecular analyses, particularly the 16S rRNA …