scholarly journals Phycobilisome isolation and C-phycocyanin purification from the cyanobacterium Aphanizomenon gracile

2019 ◽  
Vol 57 (2) ◽  
pp. 491-499 ◽  
Author(s):  
R. PIRON ◽  
T. BUSTAMANTE ◽  
A. BARRIGA ◽  
N. LAGOS
Keyword(s):  
Aphanizomenon Gracile

scholarly journals Cianobacterias en un embalse subtropical de la provincia de Salta (Argentina)

2018 ◽  
Vol 53 (4) ◽  
pp. 543-549
Author(s):  
Andrea Vidaurre ◽  
Florencia S Alvarez Dalinger ◽  
Liliana B Moraña ◽  
María M. Salusso
Keyword(s):  
Cylindrospermopsis Raciborskii ◽  
Aphanizomenon Gracile

El embalse Limón se ha convertido en la principal fuente de agua potable para el 80% de la población del norte de la provincia de Salta (22° 05’47,90’’S-63° 44’ 19,48’’ W). Al presente, no existe información sistematizada de las algas del fitoplancton presentes en esta presa. Se analizaron 19 muestras del período 2013-2015 en ambas fases del ciclo hidrológico, según técnicas estandarizadas, con el objeto de evaluar la representatividad de cianobacterias potencialmente tóxicas en Limón y su importancia relativa en el fitoplancton. Existió un predominio de cianobacterias, con un incremento interanual significativo, siendo éstas más abundantes en los estiajes, con un promedio de 110.160 células en 2015, con predominio de Cylindrospermopsis raciborskii y Raphidiopsis mediterranea (75.027 y 170.000 células/ml). Entre las especies con potencial toxicogénico se destacaron por sus densidades Anabaenopsis elenkinii,  Aphanizomenon gracile, Aphanocapsa annulata, Coelomoron tropicale, Chroococcus dispersus, C. raciborskii, Microcysis flos-aquae, Planktolyngbia limnetica, Pseudanabaena limnetica, R. mediterránea y R. curvata. La representatividad del grupo dentro del fitoplancton fue superior al 70 %. Se concluye que el cuerpo de agua es un ambiente de riesgo y debe ser monitoreado permanentemente para su empleo para agua de consumo humano.

Biocidal effect of (E)-anethole on the cyanobacterium Aphanizomenon gracile Lemmermann

2016 ◽  
Vol 29 (3) ◽  
pp. 1297-1305 ◽  
Author(s):  
Nikoletta Ntalli ◽  
Antonis Michaelakis ◽  
Kodjo Eloh ◽  
Dimitrios P Papachristos ◽  
Lukasz Wejnerowski ◽  
...  
Keyword(s):  
Aphanizomenon Gracile

scholarly journals Differences in cell wall of thin and thick filaments of cyanobacterium Aphanizomenon gracile SAG 31.79 and their implications for different resistance to Daphnia grazing

2016 ◽  
Author(s):  
Lukasz Wejnerowski ◽  
Slawek Cerbin ◽  
Maria K. Wojciechowicz ◽  
Marcin K. Dziuba
Keyword(s):  
Cell Wall ◽  
Wall Thickness ◽  
Cell Walls ◽  
Cell Wall Thickness ◽  
Filamentous Cyanobacterium ◽  
Thin Sections ◽  
Thick Filaments ◽  
Transmission Electron ◽  
The Difference ◽  
Aphanizomenon Gracile

<p>Recent studies have shown that the filamentous cyanobacterium <em>Aphanizomenon gracile</em> Lemmermann, strain SAG 31.79, consists of two types of filaments that differ in thickness. These two types are known to vary in resistance to <em>Daphnia</em> <em>magna</em> grazing: thin filaments (&lt;2.5 µm) are more vulnerable to grazing than the thick ones (&gt;2.5 µm). In this study, we investigated whether the difference in the vulnerability to grazing of thin and thick filaments is a result of different thickness of their cell walls, a filament stiffness determinant. We expected thick filaments to have thicker cell walls than the thin ones. Additionally, we analysed whether cell wall thickness correlates with filament thickness regardless of the filament type. A morphometric analysis of cell walls was performed using transmission electron micrographs of ultra-thin sections of the batch-cultured cyanobacterial material.  Our study revealed that the thin type of filaments had thinner cell walls than the thick filaments. Moreover, cell wall thickness was positively correlated with filament thickness. TEM (transmission electron microscopy) observations also revealed that the thin type of filaments was often at different stages of autocatalytic cell destruction, which was mainly manifested in the increase in cell vacuolization and degradation of the cytoplasm content. Based on our findings, we assume that previously reported higher resistance of thick filaments to <em>Daphnia</em> grazing results from greater stiffness and excellent physiological conditions of thick filaments. </p>

scholarly journals Cyanotoxin Screening in BACA Culture Collection: Identification of New Cylindrospermopsin Producing Cyanobacteria

Toxins ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 258
Author(s):  
Rita Cordeiro ◽  
Joana Azevedo ◽  
Rúben Luz ◽  
Vitor Vasconcelos ◽  
Vítor Gonçalves ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
16S Rrna ◽  
Microcystis Aeruginosa ◽  
New Genus ◽  
Culture Collection ◽  
Morphological Identification ◽  
Aphanizomenon Gracile ◽  
Toxin Producers

Microcystins (MCs), Saxitoxins (STXs), and Cylindrospermopsins (CYNs) are some of the more well-known cyanotoxins. Taking into consideration the impacts of cyanotoxins, many studies have focused on the identification of unknown cyanotoxin(s)-producing strains. This study aimed to screen strains from the Azorean Bank of Algae and Cyanobacteria (BACA) for MCs, STX, and CYN production. A total of 157 strains were searched for mcy, sxt, and cyr producing genes by PCR, toxin identification by ESI-LC-MS/MS, and cyanotoxin-producing strains morphological identification and confirmation by 16S rRNA phylogenetic analysis. Cyanotoxin-producing genes were amplified in 13 strains and four were confirmed as toxin producers by ESI-LC-MS/MS. As expected Aphanizomenon gracile BACA0041 was confirmed as an STX producer, with amplification of genes sxtA, sxtG, sxtH, and sxtI, and Microcystis aeruginosa BACA0148 as an MC-LR producer, with amplification of genes mcyC, mcyD, mcyE, and mcyG. Two nostocalean strains, BACA0025 and BACA0031, were positive for both cyrB and cyrC genes and ESI-LC-MS/MS confirmed CYN production. Although these strains morphologically resemble Sphaerospermopsis, the 16S rRNA phylogenetic analysis reveals that they probably belong to a new genus.

scholarly journals Unexpected Micro-Spatial Scale Genomic Diversity of the Bloom-Forming Cyanobacterium Aphanizomenon Gracile and its Phycosphere

2021 ◽  
Author(s):  
Sebastien Halary ◽  
Sébastien Duperron ◽  
Sandra Kim Tiam ◽  
Charlotte Duval ◽  
Eloïse Dhénain ◽  
...  
Keyword(s):  
Heterotrophic Bacteria ◽  
Hot Spot ◽  
Genotypic Diversity ◽  
Gene Clusters ◽  
Genomic Diversity ◽  
Key Factor ◽  
Colonization Success ◽  
Spatio Temporal ◽  
Water Ecosystems ◽  
Aphanizomenon Gracile

Abstract Background: Genotypic diversity within cyanobacteria populations, partly driven by horizontal gene transfers, is a key factor of their colonization success, allowing them to cope with spatio-temporal fluctuations of the environmental conditions. By providing complementary functions, such as oxidative stress protection, heterotrophic bacteria composing phycospheres play also an essential role in cyanobacteria adaptation. Aphanizomenon gracile is a species of toxinogen cyanobacteria blooming worldwide with severe consequences for fresh and brackish water ecosystems. While marker heterogeneity surveys have shown that harmful cyanobacteria blooms were not clonal populations, the real extent of genetic and functional diversity within a population of freshwater cyanobacteria, including A. gracile , and their associated phycospheres remains unclear. Results: Here, comparative omics of four monoclonal strains of A. gracile isolated from a single drop of water reveals extensive heterogeneity of chemotypes and gene contents, despite constrained genome size and high similarity indices. These variations are remarkably associated with horizontal gene transfers (HGT) of biosynthetic gene clusters (BCG), and a novel siphophage infecting A. gracile displaying characteristics of temperate phages appears to participate to this genotypic diversification. In spite of high variability in heterotrophic taxa relative abundances, A. gracile phycospheres displayed an apparent functional redundancy implying biosynthesis of public goods. Conclusions: Altogether, these results suggest that a bloom would constitute a hot-spot for A. gracile genotype diversification driven by cyanophages, where losses and gains of BCGs compels cyanobacteria individuals to cooperate together and with heterotrophic bacteria in a black queen hypothesis compatible way.

scholarly journals Temperature Influences the Production and Transport of Saxitoxin and the Expression of sxt Genes in the Cyanobacterium Aphanizomenon gracile

Toxins ◽  
2017 ◽  
Vol 9 (10) ◽  
pp. 322 ◽  
Author(s):  
Samuel Cirés ◽  
Adrián Delgado ◽  
Miguel González-Pleiter ◽  
Antonio Quesada
Keyword(s):  
Aphanizomenon Gracile

Paralytic shellfish toxin producing Aphanizomenon gracile strains isolated from Lake Iznik, Turkey

Toxicon ◽  
2018 ◽  
Vol 148 ◽  
pp. 132-142 ◽  
Author(s):  
Mete Yilmaz ◽  
Amanda J. Foss ◽  
Andrew I. Selwood ◽  
Mihriban Özen ◽  
Michael Boundy
Keyword(s):  
Paralytic Shellfish Toxin ◽  
Paralytic Shellfish ◽  
Shellfish Toxin ◽  
Aphanizomenon Gracile

scholarly journals Aphanizomenon gracile increases in width in the presence of Daphnia. A defence mechanism against grazing?

2013 ◽  
Vol 72 (3) ◽  
pp. 41 ◽  
Author(s):  
Slawek Cerbin ◽  
Łukasz Wejnerowski ◽  
Marcin Dziuba
Keyword(s):  
Defence Mechanism ◽  
Aphanizomenon Gracile

scholarly journals Paralytic Shellfish Poisoning Toxin-Producing Cyanobacterium Aphanizomenon gracile in Northeast Germany

2010 ◽  
Vol 76 (4) ◽  
pp. 1173-1180 ◽  
Author(s):  
Andreas Ballot ◽  
Jutta Fastner ◽  
Claudia Wiedner
Keyword(s):  
Paralytic Shellfish Poisoning ◽  
Water Bodies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Shellfish Poisoning ◽  
Paralytic Shellfish ◽  
Liquid Chromatography Tandem Mass ◽  
Paralytic Shellfish Poisoning Toxin ◽  
Aphanizomenon Gracile ◽  
Psp Toxins

ABSTRACT Neurotoxic paralytic shellfish poisoning (PSP) toxins, anatoxin-a (ATX), and hepatotoxic cylindrospermopsin (CYN) have been detected in several lakes in northeast Germany during the last 2 decades. They are produced worldwide by members of the nostocalean genera Anabaena, Cylindrospermopsis, and Aphanizomenon. Although no additional sources of PSP toxins and ATX have been identified in German water bodies to date, the observed CYN concentrations cannot be produced solely by Aphanizomenon flos-aquae, the only known CYN producer in Germany. Therefore, we attempted to identify PSP toxin, ATX, and CYN producers by isolating and characterizing 92 Anabaena, Aphanizomenon, and Anabaenopsis strains from five lakes in northeast Germany. In a polyphasic approach, all strains were morphologically and phylogenetically classified and then tested for PSP toxins, ATX, and CYN by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and enzyme-linked immunosorbent assay (ELISA) and screened for the presence of PSP toxin- and CYN-encoding gene fragments. As demonstrated by ELISA and LC-MS, 14 Aphanizomenon gracile strains from Lakes Melang and Scharmützel produced four PSP toxin variants (gonyautoxin 5 [GTX5], decarbamoylsaxitoxin [dcSTX], saxitoxin [STX], and neosaxitoxin [NEO]). GTX5 was the most prevalent PSP toxin variant among the seven strains from Lake Scharmützel, and NEO was the most prevalent among the seven strains from Lake Melang. The sxtA gene, which is part of the saxitoxin gene cluster, was found in the 14 PSP toxin-producing A. gracile strains and in 11 non-PSP toxin-producing Aphanizomenon issatschenkoi, A. flos-aquae, Anabaena planktonica, and Anabaenopsis elenkinii strains. ATX and CYN were not detected in any of the isolated strains. This study is the first confirming the role of A. gracile as a PSP toxin producer in German water bodies.

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