Read by QxMD icon Read

Journal of Phycology

Cristiana Callieri, Stefano Amalfitano, Gianluca Corno, Andrea Di Cesare, Roberto Bertoni, Ester Eckert
Planktonic cyanobacteria belonging to the genus Synechococcus are ubiquitously distributed in marine and fresh waters, substantially contributing to total carbon fixation on a global scale. While their ecological relevance is acknowledged, increasing resolution in molecular techniques allows disentangling cyanobacteria's role at the micro-scale, where complex microbial interactions may drive the overall community assembly. The interplay between phylogenetically different Synechococcus clades and their associated bacterial communities can affect their ecological fate and susceptibility to protistan predation...
September 15, 2017: Journal of Phycology
Urban Tillmann, Mona Hoppenrath, Marc Gottschling, Kusber Wolf-Henning, Malte Elbrächter
One of the most common marine dinophytes is a species known as Heterocapsa triquetra. When Stein introduced the taxon Heterocapsa he formally based the type species H. triquetra on the basionym Glenodinium triquetrum. The latter was described by Ehrenberg and is most likely a species of Kryptoperidinium. In addition to that currently unresolved nomenclatural situation, the thecal plate composition of H. triquetra sensu Stein (1883) was controversial in the past. In order to clarify the debate, we collected material and established the strain UTKG7 from the Baltic Sea off Kiel (Germany, the same locality as Stein had studied), which was investigated using light and electron microscopy, and whose systematic position was inferred using molecular phylogenetics...
September 15, 2017: Journal of Phycology
Kenneth Neil Mertens, Haifeng Gu, Vera Pospelova, Nicolas Chomérat, Elisabeth Nézan, Pieter Roger Gurdebeke, Kara Bogus, Henk Vrielinck, Myriam Rumebe, Claire Meteigner
The resting cysts of the benthic dinoflagellate Prorocentrum leve from a natural reservoir in Gujan-Mestras (Gironde, France) were described in this study. The incubated urn-shaped cysts gave rise to cells of Prorocentrum leve. Morphological observations through light microscopy and scanning electron microscopy, particularly of the periflagellar platelets, combined with large subunit ribosomal DNA sequences obtained through single-cell analysis confirm their affinity to the species Prorocentrum leve. The cysts are characterized by a specific shape and the presence of an anterior plug...
September 2, 2017: Journal of Phycology
Lenka Štenclová, Karolina Fučíková, Jan Kaštovský, Marie Pažoutová
The family Oocystaceae (Chlorophyta) is a group of morphologically and ultrastructurally distinct green algae that constitute a well-supported clade in the class Trebouxiophyceae. Despite the family's clear delimitation, which is based on specific cell wall features, only a few members of the Oocystaceae have been examined using data other than morphological. In previous studies of Trebouxiophyceae, after the establishment of molecular phylogeny, the taxonomic status of the family was called into question. The genus Oocystis proved to be paraphyletic and some species were excluded from Oocystaceae, while a few other species were newly redefined as members of this family...
August 18, 2017: Journal of Phycology
Mitsunobu Kamiya, Erika Saba, John A West
In animals and land plants, many asexual species originate through inter- or intraspecific crosses, and such heterozygous asexuals frequently are more abundant than their sexual relatives in marginal habitats. Although asexual species have been reported in various macroalgal taxa, detailed information regarding their distribution, heterozygosity, and origin is limited. Because many asexual tetrasporophyte strains of Caloglossa vieillardii have been isolated from South Australia, far from their core tropical habitats, we re-examined the distribution range of asexual C...
August 18, 2017: Journal of Phycology
Evelyn Lawrenz, Tammi L Richardson
The underwater light field in blackwater environments is strongly skewed toward the red end of the electromagnetic spectrum due to blue light absorption by colored dissolved organic matter (CDOM). Exposure of phytoplankton to full spectrum irradiance occurs only when cells are mixed up to the surface. We studied the potential effects of mixing-induced changes in spectral irradiance on photoacclimation, primary productivity and growth in cultures of the cryptophyte Rhodomonas salina and the diatom Skeletonema costatum...
August 16, 2017: Journal of Phycology
Blake D Ramsby, Malcolm S Hill, Daniel J Thornhill, Sieuwkje F Steenhuizen, Michelle Achlatis, Allison M Lewis, Todd C LaJeunesse
Dinoflagellates in the genus Symbiodinium associate with a broad array of metazoan and protistian hosts. Symbiodinium-based symbioses involving bioeroding sponge hosts have received less attention than those involving popular scleractinian hosts. Certain species of common Cliona harbor high densities of an ecologically restricted group of Symbiodinium, referred to as Clade G. Clade G Symbiodinium are also known to form stable and functionally important associations with Foraminifera and black corals (Antipatharia) Analyses of genetic evidence indicate that Clade G likely comprises several distinct species...
August 10, 2017: Journal of Phycology
Kazuya Takahashi, Øjvind Moestrup, Minoru Wada, Atsushi Ishimatsu, Van Nguyen Nguyen, Yasuwo Fukuyo, Mitsunori Iwataki
A new marine woloszynskioid dinoflagellate Dactylodinium pterobelotum gen. et sp. nov., collected from a southern Vietnamese estuary, was described on the basis of LM, SEM, and TEM, and molecular phylogeny inferred from rDNA sequences. This species had the smallest number of amphiesmal vesicles (5 latitudinal series) in woloszynskioid dinoflagellates assigned to the Suessiaceae and Borghiellaceae. The eyespot was of type B, composed of osmiophilic globules and brick-like material, located in- and outside of the chloroplast respectively...
August 10, 2017: Journal of Phycology
Elena Fabro, Gastón O Almandoz, Martha Ferrario, Uwe John, Urban Tillmann, Kerstin Toebe, Bernd Krock, Allan Cembella
In the Argentine Sea, blooms of toxigenic dinoflagellates of the Alexandrium tamarense species complex have led to fish and bird mortalities and human deaths as a consequence of paralytic shellfish poisoning (PSP). Yet little is known about the occurrence of other toxigenic species of the genus Alexandrium, or of their toxin composition beyond coastal waters. The distribution of Alexandrium species and related toxins in the Argentine Sea was determined by sampling surface waters on an oceanographic expedition during austral spring from ~39°S to 48°S...
August 9, 2017: Journal of Phycology
Michael J Braus, Linda E Graham, Thea L Whitman
The branched periphytic green alga Cladophora glomerata, often abundant in nearshore waters of lakes and rivers worldwide, plays important ecosystem roles, some mediated by epibiotic microbiota that benefit from host-provided surface, organic C, and O2 . Previous microscopy and high-throughput sequencing studies have indicated surprising epibiont taxonomic and functional diversity, but have not included adequate consideration of sample replication or the potential for spatial and temporal variation. Here, we report the results of 16S rRNA amplicon-based phylum-to-genus taxonomic analysis of Cladophora-associated bacterial epibiota sampled in replicate from three microsites and at six times during the open-water season of 2014, from the same lake locale (Picnic Point, Lake Mendota, Dane Co...
August 8, 2017: Journal of Phycology
Tamsyne Jade Smith-Harding, John Beardall, James Gordon Mitchell
Carbon dioxide concentrating mechanisms (CCMs) act to improve the supply of CO2 at the active site of ribulose-1,5-bisphosphate carboxylase/oxygenase (RUBISCO). There is substantial evidence that in some microalgal species CCMs involve an external carbonic anhydrase (CAext ) and that CAext activity is induced by low CO2 concentrations in the growth medium. However, much of this work has been conducted on cells adapted to air-equilibrium concentrations of CO2 , rather than to changing CO2 conditions caused by growing microalgal populations...
August 3, 2017: Journal of Phycology
Todd C Lajeunesse
It has been 55 years since Hugo Freudenthal described Symbiodinium microadriaticum (Dinophyceae), the type species of this large and important dinoflagellate genus found commonly in mutualistic symbiosis with cnidarians, other invertebrates, and certain protists. However, no type specimen was designated by Freudenthal, thus S. microadriaticum was invalid, as was Symbiodinium and every species subsequently assigned to the genus. The original culture was lost, but since 1979, a different culture, CCMP2464/rt-061, had been considered to represent S...
July 26, 2017: Journal of Phycology
Aaron A Heiss, Alaric W Heiss, Kaleigh Lukacs, Eunsoo Kim
Glaucophytes are a kingdom-scale lineage of unicellular algae with uniquely underived plastids. The genus Cyanophora is of particular interest because it is the only glaucophyte that is a flagellate throughout its life cycle, making its morphology more directly comparable than other glaucophytes to other eukaryote flagellates. The ultrastructure of Cyanophora has already been studied, primarily in the 1960s and 1970s. However, the usefulness of that work has been undermined by its own limitations, subsequent misinterpretations, and a recent taxonomic revision of the genus...
July 25, 2017: Journal of Phycology
Bruna Buch, Mariéllen Dornelles Martins, Luis Henrique Z Branco
Several new genera originally classified as the genus Phormidium, a polyphyletic and taxonomically complex genus within the Oscillatoriales, were recently described. The simple morphology of Phormidium does not reflect its genetic diversity and the delimitation of a natural group is not possible with traditional classification systems based on morphology alone. Therefore, this study used morphological, ecological, and molecular approaches to evaluate four populations morphologically similar to Ammassolinea, Kamptonema, and Ancylothrix (simple, curved, and gradually attenuated at the ends trichome), found in subtropical and tropical Brazilian regions...
July 24, 2017: Journal of Phycology
Ligia Collado-Vides, Alain Duran, Elizabeth Armenis, Valéria Cassano, Deron Burkepile, Andrew A Shantz, Laura Palma, Jhoana Díaz-Larrea, Abel Sentíes, Mutue Toyota Fujii
As marine tropical ecosystems deteriorate and lose biodiversity, their communities are shifting to being dominated by a few species, altering ecosystem's functioning and services. Macroalgae are becoming dominant on coral reefs, and are frequently observed outcompeting corals. Turf algal assemblages are the base of energy flow in these systems and one of the most abundant types of macroalgae on coral reefs, but little is known about their biology and diversity. Through molecular and morphological analyses, we identified the turf-forming species Laurencia cervicornis, and by studying seasonal recruitment and the impact of herbivorous fishes on its abundance, we describe its survival strategy...
July 22, 2017: Journal of Phycology
Schery Umanzor, Lydia Ladah, José A Zertuche-González
Intertidal macroalgae can modulate their biophysical environment by ameliorating physical conditions and creating habitats. Exploring how seaweed aggregations made up of different species at different densities modify the local environment may help explain how associated organisms respond to the attenuation of extreme physical conditions. Using Silvetia compressa, Chondracanthus canaliculatus and Pyropia perforata, we constructed monocultures representing the leathery, corticated and foliose functional-forms as well as a mixed tri-culture assemblage including the former three, at four different densities...
July 14, 2017: Journal of Phycology
Anchittha Satjarak, Linda E Graham
The wall-less green flagellate Pyramimonas parkeae is classified in clade I of the prasinophytes, a paraphyletic assemblage representing the last common ancestor of Viridiplantae, a monophyletic group composed of the green algae and land plants. Consequently, P. parkeae and other prasinophytes illuminate early-evolved Viridiplantae traits likely fundamental in the systems biology of green algae and land plants. Cellular structure and organellar genomes of P. parkeae are now well understood, and transcriptomic sequence data are also publically available for one strain of this species, but corresponding nuclear genomic sequence data are lacking...
July 14, 2017: Journal of Phycology
Tania Hernández Fariñas, Lourenço Ribeiro, Dominique Soudant, Catherine Belin, Cédric Bacher, Luis Lampert, Laurent Barillé
Suspended marine benthic microalgae in the water column reflect the close relationship between the benthic and pelagic components of coastal ecosystems. In this study, a 12-year phytoplankton time-series was used to investigate the contribution of benthic microalgae to the pelagic system at a site along the French-Atlantic coast. Furthermore, all taxa identified were allocated into different growth forms in order to study their seasonal patterns. The highest contribution of benthic microalgae was observed during the winter period, reaching up to 60% of the carbon biomass in the water column...
July 14, 2017: Journal of Phycology
Jun-Woo Kim, Neil M Price
Thalassiosira oceanica (CCMP 1005) was grown over a range of copper concentrations at saturating and subsaturating irradiance to test the hypothesis that Cu and light were interacting essential resources. Growth was a hyperbolic function of irradiance in Cu-replete medium (263 fmol Cu' · L(-1) ) with maximum rates achieved at 200 μmol photons · m(-2)  · s(-1) . Lowering the Cu concentration at this irradiance to 30.8 fmol Cu' · L(-1) decreased cellular Cu quota by 7-fold and reduced growth rate by 50%...
July 6, 2017: Journal of Phycology
Joseph L Richards, Thomas Sauvage, William E Schmidt, Suzanne Fredericq, Jeffery R Hughey, Paul W Gabrielson
Interspecific systematics in the red algal order Sporolithales remains problematic. To re-evaluate its species, DNA analyses were performed on historical type material and recently collected specimens assigned to the two genera Sporolithon and Heydrichia. Partial rbcL sequences from the lectotype specimens of Sporolithon ptychoides (the generitype species) and Sporolithon molle, both from El Tor, Egypt, are exact matches to field-collected topotype specimens. Sporolithon crassum and Sporolithon erythraeum also have the same type locality; material of the former appears to no longer exist, and we were unable to PCR amplify DNA from the latter...
July 6, 2017: Journal of Phycology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"