New cyanobacterium Nodosilinea svalbardensis sp. nov. (Prochlorotrichaceae, Synechococcales) isolated from alluvium in Mimer river valley of the Svalbard archipelago

Phytotaxa ◽  
2020 ◽  
Vol 442 (2) ◽  
pp. 61-79 ◽  
Author(s):  
DENIS DAVYDOV ◽  
SERGEI SHALYGIN ◽  
ANNA VILNET

A cyanobacterial strain isolated from the Svalbard archipelago was studied using morphological, ecological, and molecular approaches. The morphology of natural populations fit well the description of the Leptolyngbya s.l. however, in culture, they formed specific nodules that prevented affiliation to this genus. Further phylogenetic analyses including the 16S rRNA gene and 16S-23S ITS region revealed that the strain corresponds to the genus Nodosilinea. Based on this total evidence approach, we provide here a description of the new taxon Nodosilinea svalbardensis sp. nov.

Phytotaxa ◽  
2018 ◽  
Vol 334 (2) ◽  
pp. 167 ◽  
Author(s):  
JUAN VÁZQUEZ-MARTÍNEZ ◽  
JUAN MANUEL GUTIERREZ-VILLAGOMEZ ◽  
CITLALI FONSECA-GARCÍA ◽  
ENRIQUE RAMÍREZ-CHÁVEZ ◽  
MA. LOURDES MONDRAGÓN-SÁNCHEZ ◽  
...  

Microorganisms of subaerial biofilms, which develop on the surface of stone monuments, have been widely studied due to their impact on Cultural Heritage deterioration. Nevertheless, these extremophile microorganisms are poorly characterised. In this study, a cyanobacterial strain isolated from an archaeological zone in north-central Mexico was characterised through a polyphasic study based on ecological, morphological, and molecular data. Phylogenetic analyses were done using sequences of the 16S rRNA gene and the 16S-23S ITS region. Based on the polyphasic data, a new species corresponding to the genus Nodosilinea is described. This alkaliphilic species has optimum growth at pH of 9. Its fatty acid profile indicates that C18:1, 9E and C16:0 are its most abundant fatty acids. Extracellular polymeric substance production was verified on this strain. Only a few species of the genus Nodosilinea have been documented and described, and this is the first report of their presence in central Mexico. Hence the name Nodosilinea chupicuarensis sp. nov. is proposed.


Phytotaxa ◽  
2014 ◽  
Vol 163 (5) ◽  
pp. 241 ◽  
Author(s):  
Radka Muhlsteinova ◽  
Jeffrey R. Johansen ◽  
Nicole Pietrasiak ◽  
Michael P. Martin ◽  
Karina Osorio-Santos ◽  
...  

Little is known about the taxonomic diversity of cyanobacteria in deserts, despite their important ecological roles in these ecosystems. In this study, cyanobacterial strains from the Atacama, Colorado, and Mojave Deserts were isolated and characterized using molecular, morphological, and ecological information. Phylogenetic placement of these strains was revealed through Bayesian and parsimony-based phylogenetic analyses utilizing sequences of the 16S rRNA gene and the associated 16S–23S ITS region. Based on the combined evidence of this polyphasic approach, a new species from desert soils morphologically corresponding to the genus Trichocoleus was described. Trichocoleus desertorum sp. nov. Mühlsteinová, Johansen et Pietrasiak was used to obtain a phylogenetic reference point for Trichocoleus, a genus so far characterized by morphological description only. Through characterization of this new taxon in desert soils we hope to contribute to the general understanding of cyanobacterial diversity in extreme arid habitats.


Phytotaxa ◽  
2016 ◽  
Vol 266 (2) ◽  
pp. 134 ◽  
Author(s):  
QI ZHAO ◽  
YAN-JIA HAO ◽  
JIAN-KUI LIU ◽  
KEVIN D. HYDE ◽  
YANG-YANG CUI ◽  
...  

Infundibulicybe rufa sp. nov., is described from Jiuzhaigou Biosphere Reserve, southwestern China. It is characterized by the combination of the following characters: umbilicate to slightly infundibuliform, reddish brown pileus; decurrent, cream lamellae; cylindrical stipe concolorous with the pileus surface. Molecular phylogenetic analyses using the nuclear ribosomal internal transcribed spacer (ITS) region indicates that I. rufa is closely related to I. mediterranea and I. bresadolana. A description, line drawings, phylogenetic placement and comparison with allied taxa for the new taxon are presented.


2005 ◽  
Vol 55 (1) ◽  
pp. 245-250 ◽  
Author(s):  
Pierre Juteau ◽  
Valérie Côté ◽  
Marie-France Duckett ◽  
Réjean Beaudet ◽  
François Lépine ◽  
...  

An anaerobic bacterium that transforms phenol and 4-hydroxybenzoate (4-OHB) into benzoate, strain LR7.2T, was isolated from a culture originating from a mixture of swamp water, sewage sludge, swine waste and soil. Cells of strain LR7.2T are Gram-positive short rods (1×2 μm) that are electron-dense when observed by electron microscopy. The optimum pH and temperature for growth and transformation activity of 4-OHB are 7·5–8·0 and 30–37 °C, respectively. The bacterium does not use sulphate, thiosulphate, nitrate, nitrite, FeCl3, fumarate or arsenate as an electron acceptor. It does not normally use sulphite, although stimulation of growth and 4-OHB transformation activity at a low concentration (up to 2 mM) has been reported previously under different culture conditions. The presence of 4-OHB or phenol is essential for growth; transformation of 4-OHB or phenol into benzoate is used to produce energy for growth. Using [6D]-phenol, 4-OHB was shown to be an intermediate in the transformation of phenol into benzoate. No spore was observed. The bacterium has a DNA G+C content of 51 mol% and its major membrane fatty acid is anteiso-C15 : 0. The 16S rRNA gene sequence of strain LR7.2T shows only 90 % similarity to its closest relative (Pelotomaculum thermopropionicum). From these results, a new taxon is proposed: Cryptanaerobacter phenolicus gen. nov., sp. nov. The type strain is LR7.2T (=ATCC BAA-820T=DSM 15808T).


1995 ◽  
Vol 347 (1320) ◽  
pp. 213-234 ◽  

Phylogenedc reladonships of higher taxa of echinoids have been invesdgated using a 163 character morphological data base and molecular sequences from large and small subunit (LSU and SSU) ribosomal RNA (rRNA) genes. The complete ssu rRNA gene has been sequenced for 21 taxa, with representatives from nine of the 14 extant orders of Echinoidea. Partial LSU sequences, representing the first 400 base pairs (b.p.) from the 5' end were also sequenced for three taxa to complement an existing data base of ten taxa. The two molecular sequences provided a total of 371 variable sites, of which 143 were phylogenetically informative (compared to 145 phylogenetically informative sites from morphological data). Morphological, LSU and SSU data have been analysed separately and together. Morphological and ssu sequence data generate topologies that are not significantly in conflict (under Templeton’s test), but the strong signal pairing arbaciids with clypeasteroids in the LSU derived tree marks the LSU sequence data as anomalous for this taxon. A ‘ total evidence’ approach derived a tree very similar in topology to that derived from morphological data. Rooted on the stem group echinoid Archaeocidaris , our total evidence tree suggested relationships of higher taxa as follows: Gidaroida Phormosomatidae Echinothuriidae Diadematidae Spatangoida Clypeasteroida, Cassiduloida Calycina, Arbacioida Stomopneustidae Glyphocidaridae Temnopleuridae Echinometridae Echinidae, Strongylocentridae. Phylogenetic analyses run both with and without key fossil taxa yielded slightly different topologies. It is important to include fossil taxa in a phylogenetic analysis where there are long stem-group branches or where the crown group is highly derived.


2004 ◽  
Vol 54 (1) ◽  
pp. 175-181 ◽  
Author(s):  
Costantino Vetriani ◽  
Mark D. Speck ◽  
Susan V. Ellor ◽  
Richard A. Lutz ◽  
Valentin Starovoytov

A thermophilic, anaerobic, chemolithoautotrophic bacterium was isolated from the walls of an active deep-sea hydrothermal vent chimney on the East Pacific Rise at 9° 50′ N. Cells of the organism were Gram-negative, motile rods that were about 1·0 μm in length and 0·6 μm in width. Growth occurred between 60 and 80 °C (optimum at 75 °C), 0·5 and 4·5 % (w/v) NaCl (optimum at 2 %) and pH 5 and 7 (optimum at 5·5). Generation time under optimal conditions was 1·57 h. Growth occurred under chemolithoautotrophic conditions in the presence of H2 and CO2, with nitrate or sulfur as the electron acceptor and with concomitant formation of ammonium or hydrogen sulfide, respectively. Thiosulfate, sulfite and oxygen were not used as electron acceptors. Acetate, formate, lactate and yeast extract inhibited growth. No chemoorganoheterotrophic growth was observed on peptone, tryptone or Casamino acids. The genomic DNA G+C content was 54·6 mol%. Phylogenetic analyses of the 16S rRNA gene sequence indicated that the organism was a member of the domain Bacteria and formed a deep branch within the phylum Aquificae, with Thermovibrio ruber as its closest relative (94·4 % sequence similarity). On the basis of phylogenetic, physiological and genetic considerations, it is proposed that the organism represents a novel species within the newly described genus Thermovibrio. The type strain is Thermovibrio ammonificans HB-1T (=DSM 15698T=JCM 12110T).


2006 ◽  
Vol 188 (9) ◽  
pp. 3345-3356 ◽  
Author(s):  
Craig Everroad ◽  
Christophe Six ◽  
Frédéric Partensky ◽  
Jean-Claude Thomas ◽  
Julia Holtzendorff ◽  
...  

ABSTRACT Chromatic adaptation (CA) in cyanobacteria has provided a model system for the study of the environmental control of photophysiology for several decades. All forms of CA that have been examined so far (types II and III) involve changes in the relative contents of phycoerythrin (PE) and/or phycocyanin when cells are shifted from red to green light and vice versa. However, the chromophore compositions of these polypeptides are not altered. Some marine Synechococcus species strains, which possess two PE forms (PEI and PEII), carry out another type of CA (type IV), occurring during shifts from blue to green or white light. Two chromatically adapting strains of marine Synechococcus recently isolated from the Gulf of Mexico were utilized to elucidate the mechanism of type IV CA. During this process, no change in the relative contents of PEI and PEII was observed. Instead, the ratio of the two chromophores bound to PEII, phycourobilin and phycoerythrobilin, is high under blue light and low under white light. Mass spectroscopy analyses of isolated PEII α- and β-subunits show that there is a single PEII protein type under all light climates. The CA process seems to specifically affect the chromophorylation of the PEII (and possibly PEI) α chain. We propose a likely process for type IV CA, which involves the enzymatic activity of one or several phycobilin lyases and/or lyase-isomerases differentially controlled by the ambient light quality. Phylogenetic analyses based on the 16S rRNA gene confirm that type IV CA is not limited to a single clade of marine Synechococcus.


2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Roman Labuda ◽  
Andreas Bernreiter ◽  
Doris Hochenauer ◽  
Christoph Schüller ◽  
Alena Kubátová ◽  
...  

A new species, Saksenaea dorisiae (Mucoromycotina, Mucorales), isolated from a water sample originating from a private well in Manastirica, Petrovac, in the Republic of Serbia (Europe), is described and illustrated. The new taxon is well supported by multilocus phylogenetic analysis that included the internal transcribed spacer (ITS) region, domains D1 and D2 of the 28S rRNA gene (LSU), and translation elongation factor-1α gene (tef-1α), and it is resolved in a clade with S. oblongispora and S. trapezispora. This fungus is characterized by its moderately slow growth at 15 and 37°C, sparse rhizoids, conical-shaped sporangia, and short-cylindrical sporangiospores. Saksenaea dorisiae is a member of the opportunistic pathogenic genus often involved in severe human and animal mucormycoses encountered in tropical and subtropical regions. Despite its sensitivity to several conventional antifungals (terbinafine and ciclopirox), the fungus can potentially evoke clinically challenging infections. This is the first novel taxon of the genus Saksenaea described from the moderately continental climate area of Europe.


Phytotaxa ◽  
2020 ◽  
Vol 440 (2) ◽  
pp. 108-128 ◽  
Author(s):  
SERGEI SHALYGIN ◽  
REGINA R. SHALYGINA ◽  
VERA V. REDKINA ◽  
CORY B. GARGAS ◽  
JEFFREY R. JOHANSEN

Stenomitos is a recently established cyanobacterial genus, some species of which appear to be cryptic. Here we describe two new species in this genus, Stenomitos kolaensis sp. nov. isolated from the Al-Fe humic podzols of a boreal forest near Nikel town, Murmansk region, Russia and S. hiloensis sp. nov. isolated from a basaltic seep wall on Akeola Road, Hilo, Hawaii, USA. Phylogenetic analyses were conducted on the 16S and 16S-23S ITS rRNA gene regions using Bayesian Inference, and Maximum Likelihood. Phylogenetic analysis of the 16S-23S ITS rRNA region resulted in both S. kolaensis and S. hiloensis forming separate clades from other Stenomitos lineages. Antarctic strains of Stenomitos frigidus (previously reported as “Leptolyngbya frigida”) show that species to be polyphyletic and in need of revision. The structure of the conserved ITS regions (Box-B, D1-D1ʹ, V2 and V3 helices) provided support for separation of the species, and the p-distances among aligned ITS regions further confirmed that a number of species exist within the genus. S. kolaensis and S. hiloensis can be distinguished from other described Stenomitos species (S. rutilans and S. tremulus) by their geographical distribution, habitat preference, 16S rRNA phylogeny, and differences in the secondary structure of the 16S-23S ITS region.


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