Category: Dinoflagellate genomics

A novel fragmented mitochondrial genome in the protist pathogen Toxoplasma gondii and related tissue coccidia

Mitochondrial genome content and structure vary widely across the eukaryotic tree of life, with protists displaying extreme examples. Apicomplexan and dinoflagellate protists have evolved highly reduced mitochondrial genome sequences, mtDNA, consisting of only three cytochrome genes and fragmented rRNA genes. Here, we report the independent evolution of fragmented cytochrome genes in Toxoplasma and related tissue coccidia and evolution of a novel genome architecture consisting minimally of 21…

A novel fragmented mitochondrial genome in the protist pathogen Toxoplasma gondii and related tissue coccidia

Mitochondrial genome content and structure vary widely across the eukaryotic tree of life, with protists displaying extreme examples. Apicomplexan and dinoflagellate protists have evolved highly reduced mitochondrial genome sequences, mtDNA, consisting of only three cytochrome genes and fragmented rRNA genes. Here, we report the independent evolution of fragmented cytochrome genes in Toxoplasma and related tissue coccidia and evolution of a novel genome architecture consisting minimally of 21…

Sulfitobacter alexandrii sp. nov., a new microalgae growth-promoting bacterium with exopolysaccharides bioflocculanting potential isolated from marine phycosphere

Marine phycosphere harbors unique cross-kingdom associations with enormous ecological significance in aquatic ecosystems as well as relevance for algal biotechnology industry. During our investigating the microbial composition and bioactivity of marine phycosphere microbiota (PM), a novel lightly yellowish and versatile bacterium designated strain AM1-D1^(T) was isolated from cultivable PM of marine dinoflagellate Alexandrium minutum amtk4 that produces high levels of paralytic shellfish…

Comparison of 15 dinoflagellate genomes reveals extensive sequence and structural divergence in family Symbiodiniaceae and genus Symbiodinium

CONCLUSIONS: Our results underscore the potential impact of lifestyle on lineage-specific gene-function innovation, genome divergence, and the diversification of Symbiodinium and Symbiodiniaceae. The divergent features we report, and their putative causes, may also apply to other microbial eukaryotes that have undergone symbiotic phases in their evolutionary history.

Comparative Genomics and Environmental Distribution of Large dsDNA Viruses in the Family Asfarviridae

The family Asfarviridae is a group of nucleo-cytoplasmic large DNA viruses (NCLDVs) of which African swine fever virus (ASFV) is well-characterized. Recently the discovery of several Asfarviridae members other than ASFV has suggested that this family represents a diverse and cosmopolitan group of viruses, but the genomics and distribution of this family have not been studied in detail. To this end we analyzed five complete genomes and 35 metagenome-assembled genomes (MAGs) of viruses from this…

Opportunistic bacteria with reduced genomes are effective competitors for organic nitrogen compounds in coastal dinoflagellate blooms

CONCLUSIONS: The results suggest that the enriched DOM in stationary phase of phytoplankton bloom is a result of ammonium depletion. This environment drives genomic streamlining of opportunistic bacteria to exploit their preferred nitrogen-containing compounds and maintain nutrient cycling. Video abstract.

Opportunistic bacteria with reduced genomes are effective competitors for organic nitrogen compounds in coastal dinoflagellate blooms

CONCLUSIONS: The results suggest that the enriched DOM in stationary phase of phytoplankton bloom is a result of ammonium depletion. This environment drives genomic streamlining of opportunistic bacteria to exploit their preferred nitrogen-containing compounds and maintain nutrient cycling. Video abstract.

Marinobacter alexandrii sp. nov., a novel yellow-pigmented and algae growth-promoting bacterium isolated from marine phycosphere microbiota

The marine phycosphere harbors unique cross-kingdom associations with ecological relevance. During investigating the diversity of phycosphere microbiota of marine harmful algal blooms dinoflagellates, a faint yellow-pigmented bacterium, designated as strain LZ-8, was isolated from paralytic shellfish poisoning toxin-producing dinoflagellate Alexandrium catenella LZT09. The new isolate appeared to have growth-promoting potential toward its algal host. Molecular analysis using 16S rRNA gene,…

Combined characterization of a new member of Marivita cryptomonadis strain LZ-15-2 isolated from cultivable phycosphere microbiota of highly toxic HAB dinoflagellate Alexandrium catenella LZT09

During our conveying the microbial structures of phycosphere microbiota (PM) derived from diverse marine harmful algal bloom (HAB) dinoflagellates, a new rod-sharped, white-colored cultivable bacterial strain, designated as LZ-15-2, was isolated from the PM of highly toxic Alexandrium catenella LZT09. Phylogenetic analysis of 16S rRNA gene sequence indicated that strain LZ-15-2 belonged to the genus Marivita within the family Rhodobacteraceae, and demonstrated the highest gene similarity of…

Muricauda amphidinii sp. nov., a novel marine bacterium isolated from the phycosphere of dinoflagellate Amphidinium carterae

A Gram-stain-negative, aerobic, rod-shaped and non-motile bacterium was isolated from a liquid culture of dinoflagellate Amphidinium carterae and further designated as LMIT004^(T). Optimal growth was observed at 25 °C, pH 7.0 and in the presence of 2 % (w/v) NaCl. Oxidase and catalase were positive. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LMIT004^(T) showed high similarities to type strains Muricauda nanhaiensis SM17004^(T) (96.77 %) and Muricauda aquimarina…