393 results match your criteria zoospores study

Parasite-mediated increase in prey edibility in the predator-prey interaction of marine planktonic protists.

Harmful Algae 2021 Mar 3;103:101982. Epub 2021 Feb 3.

Research Institute for Basic Sciences, Chonnam National University, Gwangju 61186, Republic of Korea. Electronic address:

In planktonic predator-prey interactions, predation pressure could be affected by several factors associated with prey, including cell size, shape, nutritional quality, presence of chemical deterrents, and movement behaviors. In addition, parasitism may also play an important role in predator-prey interaction by infecting one or both partners involved in the biological interaction. In this study, parasite mediation in predator-prey interactions of planktonic protists was addressed using model organisms commonly observed in temperate coastal environments, namely, a phototrophic dinoflagellate Akashiwo sanguinea as a potential host and prey, a heterotrophic dinoflagellate predator Luciella masanensis, and a dinoflagellates-infecting parasitoid Parvilucifera infectans. Read More

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Retrospective multifactorial analysis of and review of literature.

Indian J Ophthalmol 2021 May;69(5):1095-1101

Department of Microbiology, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Cuddalore Main Road, Thavalukuppam, Pondicherry, India.

Purpose: The aim of this work was to study the demographic profile, clinical diagnostic features, challenges in management, treatment outcomes, and ocular morbidity of microbiological culture-proven Pythium keratitis in a tertiary eye care hospital in South India.

Methods: Retrospective analysis of microbiologically proven Pythium keratitis patients was performed at a tertiary eye center from October 2017 to March 2020. Demographic details, risk factors, microbiological investigations, clinical course, and visual outcomes were analyzed. Read More

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Anti-oomycetes and immunostimulatory activity of natural plant extract compounds against Saprolegnia spp.: Molecular docking and in-vitro studies.

Fish Shellfish Immunol 2021 Apr 23;114:65-81. Epub 2021 Apr 23.

ICAR- Central Institute of Fisheries Education, Andheri, Mumbai, 400036, India.

This study aimed to investigate the effectiveness of five natural plant extract compounds Curcumin (CUR); Eugenol (EUG), Cinnamaldehyde (CIN), Stigmasterol (ST) and Morin (MOR), on two species of Saprolegnia; Saprolegnia parasitica and S. australis. Selective compounds were screened for the minimum inhibitory concentration, first for anti-oomycetes activity and then mycelium growth inhibition, spore germination inhibition and colonisation test. Read More

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The Mitogen-Activated Protein Kinase PlMAPK2 Is Involved in Zoosporogenesis and Pathogenicity of .

Int J Mol Sci 2021 Mar 29;22(7). Epub 2021 Mar 29.

Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Department of Plant Pathology, South China Agricultural University, Guangzhou 510642, China.

As an evolutionarily conserved pathway, mitogen-activated protein kinase (MAPK) cascades function as the key signal transducers that convey information by protein phosphorylation. Here we identified as one of 14 predicted MAPKs encoding genes in the plant pathogenic oomycete . is conserved in and species. Read More

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Watanabeales ord. nov. and twelve novel species of Trebouxiophyceae (Chlorophyta).

J Phycol 2021 Mar 13. Epub 2021 Mar 13.

Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.

The Trebouxiophyceae include Chlorellales, Prasiolales, Trebouxiales, Microthamniales, and numerous members for which taxonomic locations have not been determined. The Watanabea clade is a group in the Trebouxiophyceae of Chlorella-like taxa, which are predominantly solitary and terrestrial. With the increase in descriptions of new species within the Watanabea clade in recent years, it is necessary to define the boundary and taxonomic status of the clade. Read More

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Erection of a New Genus and Species for the Pathogen of Hard Clams 'Quahog Parasite Unknown' (QPX): Mucochytrium quahogii gen. nov., sp. nov.

Protist 2021 02 29;172(1):125793. Epub 2021 Jan 29.

School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000, USA. Electronic address:

Quahog Parasite Unknown (QPX) is a facultative parasite of the hard clam, Mercenaria mercenaria. Although it has been observed in clams since the 1960's and cultivated since the 1990's, conflicting reports on important aspects of its biology have prevented its formal description. 18S rRNA gene sequences identify QPX as a thraustochytrid, but its production of copious mucus is atypical for this group. Read More

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February 2021

The actin networks of chytrid fungi reveal evolutionary loss of cytoskeletal complexity in the fungal kingdom.

Curr Biol 2021 Mar 8;31(6):1192-1205.e6. Epub 2021 Feb 8.

Department of Biology, University of Massachusetts, 611 N. Pleasant Street, Amherst, MA 01003, USA. Electronic address:

Cells from across the eukaryotic tree use actin polymer networks for a wide variety of functions, including endocytosis, cytokinesis, and cell migration. Despite this functional conservation, the actin cytoskeleton has undergone significant diversification, highlighted by the differences in the actin networks of mammalian cells and yeast. Chytrid fungi diverged before the emergence of the Dikarya (multicellular fungi and yeast) and therefore provide a unique opportunity to study actin cytoskeletal evolution. Read More

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Characterization and proteome analysis of the extracellular vesicles of Phytophthora capsici.

J Proteomics 2021 04 3;238:104137. Epub 2021 Feb 3.

China Agricultural University, Beijing 100193, China; State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, China. Electronic address:

Extracellular vesicles (EVs) are important for the transport of biomolecular materials and intercellular communication in eukaryotes. Recent research has revealed that they are involved in plant-pathogen interaction and pathogenesis of infected cells. Phytophthora capsici is a highly devastating oomycete pathogen with a broad host range. Read More

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Antibacterial and antioomycete activities of a novel designed RY12WY peptide against fish pathogens.

Microb Pathog 2020 Dec 23;149:104591. Epub 2020 Oct 23.

ICAR-Central Institute of Fisheries Education, Mumbai, 400061, Maharashtra, India.

In the present study, we have designed and synthesized a short compositionally simple peptide RY12WY having potent antimicrobial activity. The molecular docking study results showed that peptide has a strong affinity towards two protein targets of A. sobria; aerolysin and outer membrane protein (OMP). Read More

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December 2020

Novel Sources of Resistance to on Pepper ( sp.) Landraces from Mexico.

Plant Pathol J 2020 Dec;36(6):600-607

Independent Researcher, Dakar, Senegal, C.P. 10200, México.

Leonian is a major pathogen of pepper worldwide and few resistance sources to this pathogen have been identified so far. The goals of this study were to identify new sources of resistance against in landraces and analyze the relationship between the resistance indicator of plant symptoms and some plant phenotype parameters of plant height, stem width, leaf length and leaf width. Thirtytwo landraces of pepper were collected from fourteen states in Mexico. Read More

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December 2020

Comparing the Infection Biology of in Clubroot Susceptible and Resistant Hosts and Non-hosts.

Front Microbiol 2020 16;11:507036. Epub 2020 Oct 16.

Department of Biology, University of Saskatchewan, Saskatoon, SK, Canada.

The potential infection biology of in resistant hosts and non-hosts is still not completely understood. Clubroot resistance assay on European clubroot differentials (ECD) set revealed that ECD10 () and ECD4 () show a complete resistance to the tested isolate in contrast to highly susceptible hosts Westar () and ECD5 (). Previously, we used fluorescent probe-based confocal microscopy (FCM) to refine the life cycle of and indicate the important time points during its infection in . Read More

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October 2020

Reproductive Output, Synchrony across Depth and Influence of Source Depth in the Development of Early Life stages of Kelp.

J Phycol 2021 02 18;57(1):311-323. Epub 2020 Dec 18.

School of Biological Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia.

Ecklonia radiata is the main foundation species in Australian temperate reefs, yet little has been published on its reproduction and how this may change across its depth range (1-50+ m). In this study, we examined differences in sporophyte morphology and zoospore production during a reproductive season and across four depths (7, 15, 25, and 40 m). Additionally, we examined differences in germination rate, survival, and morphological traits of gametophytes obtained from these four depths, cultured under the same light and temperature conditions. Read More

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February 2021

Microbial Origin of Aquaponic Water Suppressiveness against Lettuce Root Rot Disease.

Microorganisms 2020 Oct 29;8(11). Epub 2020 Oct 29.

Integrated and Urban Plant Pathology Laboratory, Gembloux Agro-Bio Tech, University of Liège, 5030 Gembloux, Belgium.

Aquaponic systems are an integrated way to produce fish and plants together with mutual benefits. Fish provide nutrients to plants on the one side, and plant nutrients uptake allow water reuse for fish on the other side. In this kind of system, the use of phytosanitary treatments to control plant pathogens is sensitive because of the risk of toxicity for fish present in the same water loop, especially coupled aquaponics. Read More

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October 2020

Parasitic Chytrids Upgrade and Convey Primary Produced Carbon During Inedible Algae Proliferation.

Protist 2020 11 16;171(5):125768. Epub 2020 Sep 16.

WasserCluster - Biologische Station Lunz, Inter-university Center for Aquatic Ecosystem Research, Dr. Carl Kupelwieser Promenade 5, A-3293 Lunz am See, Austria.

Microbial parasites have only recently been included in planktonic food web studies, but their functional role in conveying dietary energy still remains to be elucidated. Parasitic fungi (chytrids) infecting phytoplankton may constitute an alternative trophic link and promote organic matter transfer through the production of dissemination zoospores. Particularly, during proliferation of inedible or toxic algal species, such as large Cyanobacteria fostered by global warming, parasites can constitute an alternative trophic link providing essential dietary nutrients that support somatic growth and reproduction of consumers. Read More

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November 2020

Microfluidic platform for integrated compartmentalization of single zoospores, germination and measurement of protrusive force generated by germ tubes.

Lab Chip 2020 11;20(22):4141-4151

Biomolecular Interaction Centre, Department of Electrical and Computer Engineering, University of Canterbury, New Zealand. and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand.

This paper describes the design, fabrication and characterisation of a novel monolithic lab-on-a-chip (LOC) platform combining the trapping and germination of individual zoospores of the oomycete Achlya bisexualis with elastomeric micropillar-based protrusive force sensing. The oomycetes are of significant interest due to their pathogenic capabilities, which can have profound ecological and economic impacts. Zoospore encystment and germination via a germ tube play a key role in their pathogenicity. Read More

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November 2020

Invertases in Phytophthora infestans Localize to Haustoria and Are Programmed for Infection-Specific Expression.

mBio 2020 10 13;11(5). Epub 2020 Oct 13.

Department of Microbiology and Plant Pathology, University of California, Riverside, California, USA

The oomycete , the causal agent of potato and tomato blight, expresses two extracellular invertases. Unlike typical fungal invertases, the genes are not sucrose induced or glucose repressed but instead appear to be under developmental control. Transcript levels of both genes were very low in mycelia harvested from artificial medium but high in preinfection stages (sporangia, zoospores, and germinated cysts), high during biotrophic growth in leaves and tubers, and low during necrotrophy. Read More

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October 2020

Root Border Cells and Mucilage Secretions of Soybean, (Merr) L.: Characterization and Role in Interactions with the Oomycete .

Cells 2020 09 30;9(10). Epub 2020 Sep 30.

Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, UPRES-EA 4358, Fédération de Recherche « Normandie-Végétal »-FED 4277, Université de ROUEN Normandie, UFR des Sciences et Techniques, F-76821 Mont-Saint-Aignan, France.

Root border cells (BCs) and their associated secretions form a protective structure termed the root extracellular trap (RET) that plays a major role in root interactions with soil borne microorganisms. In this study, we investigated the release and morphology of BCs of using light and cryo-scanning electron microscopy (SEM). We also examined the occurrence of cell-wall glycomolecules in BCs and secreted mucilage using immunofluorescence microscopy in conjunction with anti-glycan antibodies. Read More

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September 2020

New pelagophytes show a novel mode of algal colony development and reveal a perforated theca that may define the class.

J Phycol 2021 04 1;57(2):396-411. Epub 2020 Dec 1.

School of BioSciences, University of Melbourne, Melbourne, Victoria, 3010, Australia.

Pelagophytes (Heterokonta) are a morphologically diverse class of marine algae historically united only by DNA sequences. We established clonal cultures of sand-dwelling pelagophytes collected from intertidal pools around Australia. Phylogenetic trees based on nuclear 18S rDNA and plastid rbcL, psaA, psaB, psbA, and psbC sequences revealed two new genera, Gazia and Glomerochrysis, related to Aureoumbra in a distinct lineage within the Sarcinochrysidaceae (Pelagophyceae). Read More

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Development of a simple host-free medium for efficient prezoosporulation of Perkinsus olseni trophozoites cultured in vitro.

Parasitol Int 2021 Feb 9;80:102186. Epub 2020 Sep 9.

Laboratory of Fish Diseases, Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan. Electronic address:

The parasitizing stage (trophozoite) of the protozoan parasite Perkinsus olseni progresses to the dormant stage (prezoosporangium) immediately after the death of the host through physiologically and morphologically drastic changes. This development is reproducible in Ray's fluid thioglycollate medium (RFTM). In this study, supplementation with tissue extract from a host, the Manila clam, significantly improved the efficiency of development, as determined by the numbers and sizes of developed prezoosporangia. Read More

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February 2021

., a cultivable holocarpic parasitoid of the early-diverging .

A T Buaya M Thines

Fungal Syst Evol 2020 Dec 16;6:129-137. Epub 2020 Apr 16.

Goethe-Universität Frankfurt am Main, Department of Biological Sciences, Institute of Ecology, Evolution and Diversity, Max-von-Laue-Str. 13, D-60438 Frankfurt am Main, Germany.

Holocarpic oomycetes convert their entire cytoplasm into zoospores and thus do not form dedicated sporangia or hyphal compartments for asexual reproduction. The majority of holocarpic oomycetes are obligate parasites and parasitoids of a diverse suite of organisms, among them green and red algae, brown seaweeds, diatoms, fungi, oomycetes and invertebrates. Most of them are found among the early diverging oomycetes or the , and some in the early-diverging (). Read More

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December 2020

Evaluating environmental DNA as a tool for detecting an amphibian pathogen using an optimized extraction method.

Oecologia 2020 Oct 2;194(1-2):267-281. Epub 2020 Sep 2.

Department of Biological Science, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA.

Environmental DNA (eDNA) detection is a valuable conservation tool that can be used to identify and monitor imperiled or invasive species and wildlife pathogens. Batrachochytrium pathogens are of global conservation concern because they are a leading cause of amphibian decline. While eDNA techniques have been used to detect Batrachochytrium DNA in the environment, a systematic comparison of extraction methods across environmental samples is lacking. Read More

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October 2020

The RPA190-pc gene participates in the regulation of metalaxyl sensitivity, pathogenicity and growth in Phytophthora capsici.

Gene 2021 Jan 26;764:145081. Epub 2020 Aug 26.

College of Plant Protection, Anhui Agricultural University, 130 West of Changjiang Road, Hefei 230036, Anhui, China. Electronic address:

Metalaxyl is one of the main fungicides used to control pepper blight caused by Phytophthora capsici. Metalaxyl resistance of P. capsici, caused by the long-term intense use of this fungicide, has become one of the most serious challenges facing pest management. Read More

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January 2021

The microalga Haematococcus lacustris (Chlorophyceae) forms natural biofilms in supralittoral White Sea coastal rock ponds.

Planta 2020 Aug 10;252(3):37. Epub 2020 Aug 10.

Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, Moscow, 119192, Russia.

Main Conclusion: Haematococcus lacustris inhabits supralittoral rock ponds and forms, under natural conditions, biofilms including layered cyanobacterial and fermentative microbial mats. Dry mats, formed under extremely stressful conditions, contained only haematocysts. Under favorable growth conditions, modeled for dry biofilms in vitro, microalgal free-living stages were detected. Read More

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Scanning electron microscopic observation of the in vitro cultured protozoan, Perkinsus olseni, isolated from the Manila clam, Ruditapes philippinarum.

BMC Microbiol 2020 08 3;20(1):238. Epub 2020 Aug 3.

Department of Aquatic Life Medicine, College of Ocean Science and Technology, Kunsan National University, 558 Daehakno, Gunsan, 54150, Republic of Korea.

Background: Perkinsosis is a major disease affecting the commercially important marine mollusk Ruditapes philippinarum (Manila clam) in Asian waters. In this study, we investigated the morphological characteristics of Perkinsus olseni, the causative agent of perkinsosis, cultured under laboratory conditions at different stages of its life cycle using a scanning electron microscope (SEM).

Results: The prezoosporangia formed after induction with Ray's fluid thioglycollate medium (RFTM) developed into zoosporangia. Read More

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Transcriptomic and Ultrastructural Signatures of K-Induced Aggregation in Zoospores.

Microorganisms 2020 Jul 7;8(7). Epub 2020 Jul 7.

Université Côte d'Azur, INRAE, CNRS, ISA, 06903 Sophia Antipolis, France.

Most pathogenic oomycetes of the genus spread in water films as flagellated zoospores. Zoospores perceive and produce signals attracting other zoospores, resulting in autoaggregation in vitro or biofilm formation on plant surface. The mechanisms underlying intercellular communication and consequent attraction, adhesion and aggregation are largely unknown. Read More

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Taxonomic scheme of the order Chaetophorales (Chlorophyceae, Chlorophyta) based on chloroplast genomes.

BMC Genomics 2020 Jun 26;21(1):442. Epub 2020 Jun 26.

Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.

Background: Order Chaetophorales currently includes six families, namely Schizomeridaceae, Aphanochaetaceae, Barrancaceae, Uronemataceae, Fritschiellaceae, and Chaetophoraceae. The phylogenetic relationships of Chaetophorales have been inferred primarily based on short and less informative rDNA sequences. This study aimed to phylogenetically reconstruct order Chaetophorales and determine the taxonomic scheme, and to further understand the evolution of order Chaetophorales. Read More

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Biological Control of Gom-chwi () Phytophthora Root Rot with ObRS-5 to Suppress Zoosporangia Formation and Zoospores Germination.

Plant Pathol J 2020 Jun;36(3):244-254

Division of Agricultural Microbiology, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Korea.

Gom-chwi () is severely infected with , the causal organism of Phytophthora root rot, an economically important crop disease that needs management throughout the cultivation period. In the present study, Phytophthora root rot was controlled by using bacterial isolates from rhizosphere soils collected from various plants and screened for antagonistic activity against . A total of 172 bacterial strains were isolated, of which, 49 strains showed antagonistic activities by dual culture assay. Read More

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The Basic Leucine Zipper Transcription Factor PlBZP32 Associated with the Oxidative Stress Response Is Critical for Pathogenicity of the Lychee Downy Blight Oomycete Peronophythora litchii.

mSphere 2020 06 3;5(3). Epub 2020 Jun 3.

Department of Plant Pathology, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China

Basic leucine zipper (bZIP) transcription factors are widespread in eukaryotes, including plants, animals, fungi, and oomycetes. However, the functions of bZIPs in oomycetes are rarely known. In this study, we identified a bZIP protein possessing a special bZIP-PAS structure in , named We found that is upregulated in zoospores, in cysts, and during invasive hyphal growth. Read More

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Genetic transformation of , a resource for studying chytrid biology and evolutionary cell biology.

Elife 2020 05 11;9. Epub 2020 May 11.

Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, United States.

Chytrids are early-diverging fungi that share features with animals that have been lost in most other fungi. They hold promise as a system to study fungal and animal evolution, but we lack genetic tools for hypothesis testing. Here, we generated transgenic lines of the chytrid , and used fluorescence microscopy to explore chytrid cell biology and development during its life cycle. Read More

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In vivo effect of minocycline alone and in combination with immunotherapy against pythium insidiosum.

Vet Microbiol 2020 Apr 20;243:108616. Epub 2020 Feb 20.

Programa De Pós-Graduação Em Farmacologia, Centro De Ciências Da Saúde, Departamento De Microbiologia e Parasitologia, Universidade Federal De Santa Maria (UFSM), Santa Maria, RS, Brazil; Departamento De Medicina Veterinária Preventiva, Centro De Ciências Rurais, UFSM, Santa Maria, RS, Brazil. Electronic address:

This study examined the effect of minocycline alone and in combination with immunotherapy against pythiosis. Twenty rabbits, aged three months old and subcutaneously inoculated with Pythium insidiosum zoospores were divided into four groups (n = 5): treated with minocycline (10 mg/kg/day twice daily), treated with immunotherapy (34 mg subcutaneously every 14 days), treated with minocycline plus immunotherapy, and untreated (control group). The treatments were started 30 days after inoculation and continued for 70 days. Read More

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