The dataset comprises a whole-genome sequence of Ruegeria sp. PBVC088, a symbiotic (Gram-negative) bacterium associated with Pyrodinium bahamense var. compressum, which has been associated with harmful algal blooms in the coastal waters of west Sabah, Malaysia. Harmful algal blooms contribute to economic losses for the aquaculture industry, as well as human illnesses and fatalities due to paralytic shellfish poisoning. Bacteria-algae dynamics have posited that the interaction is potentially…
Category: Dinoflagellate genomics
Feb 24
The Caspase Homologues in Scallop Chlamys farreri and Their Expression Responses to Toxic Dinoflagellates Exposure
The cysteine aspartic acid-specific protease (caspase) family is distributed across vertebrates and invertebrates, and its members are involved in apoptosis and response to cellular stress. The Zhikong scallop (Chlamys farreri) is a bivalve mollusc that is well adapted to complex marine environments, yet the diversity of caspase homologues and their expression patterns in the Zhikong scallop remain largely unknown. Here, we identified 30 caspase homologues in the genome of the Zhikong scallop…
Feb 19
Gymnodinialimonas ceratoperidinii gen. nov., sp. nov., isolated from rare marine dinoflagellate Ceratoperidinium margalefii
A bacterial strain, designated J12C1-MA-4^(T), was isolated from liquid culture of the dinoflagellate Ceratoperidinium margalefii. The bacterium was Gram-negative, aerobic, and rod-shaped. Oxidase and catalase were positive. Optimal growth was observed at 30 °C, pH 7.0, in the presence of 1% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene and a 92 core gene set suggested that the strain J12C1-MA-4^(T) belongs to the family Rhodobacteraceae in the class Alphaproteobacteria and represents…
Feb 04
Alexandriicola marinus gen. nov., sp. nov., a new member of the family Rhodobacteraceae isolated from marine phycosphere
Two yellow-pigmented bacterial strains, LZ-14 ^(T) and ABI-LZ29, were isolated from the cultivable phycosphere microbiota of the highly toxic marine dinoflagellate Alexandrium catenella LZT09 and demonstrated obvious microalgae growth-promoting potentials toward the algal host. To elucidate the taxonomic status of the two bioactive bacterial strains, they were subjected to a polyphasic taxonomic characterization. Both strains were found to be Gram-negative, aerobic, rod-shaped and motile; to…
Feb 02
A robust approach to estimate relative phytoplankton cell abundances from metagenomes
Phytoplankton account for >45% of global primary production, and have an enormous impact on aquatic food webs and on the entire Earth System. Their members are found among prokaryotes (cyanobacteria) and multiple eukaryotic lineages containing chloroplasts. Genetic surveys of phytoplankton communities generally consist of PCR amplification of bacterial (16S), nuclear (18S) and/or chloroplastic (16S) rRNA marker genes from DNA extracted from environmental samples. However, our appreciation of…
Jan 17
First record of the spatial organization of the nucleosome-less chromatin of dinoflagellates: The nonrandom distribution of microsatellites and bipolar arrangement of telomeres in the nucleus of Gambierdiscus australes (Dinophyceae)
Dinoflagellates are a large group of protists whose exceptionally large genome is organized in permanently condensed nucleosome-less chromosomes. In this study, we examined the potential role of repetitive DNAs in both the structure of dinoflagellate chromosomes and the architecture of the dinoflagellate nucleus. Non-denaturing fluorescent in situ hybridization (ND-FSH) was used to determine the abundance and physical distribution of telomeric DNA and 16 microsatellites (1- to 4-bp repeats) in…
Jan 15
Unveiling the genomic structures and evolutionary events of the saxitoxin biosynthetic gene sxtA in the marine toxic dinoflagellate Alexandrium
Marine dinoflagellates Alexandriumare known to produce saxitoxin (STX) and cause paralytic shellfish poisoning (PSP) which can result in mortality in human. SxtA is considered a core gene for the biosynthesis of STX. However, its gene coding structure and evolutionary history have yet to be fully elucidated. Here, we determined the full-length sequences of sxtA cDNA and genomic coding regions from two toxic dinoflagellates, Alexandrium catenella (LIMS-PS-2645 and LIMS-PS-2647) andA. pacificum…
Jan 11
Patchy Distribution of GTPases of Immunity Associated Proteins (GIMAP) within Cnidarians and Dinoflagellates Suggests a Complex Evolutionary History
GTPases of Immunity Associated Proteins (GIMAP) are a group of small GTP binding proteins found in a variety of organisms, including vertebrates, invertebrates, and plants. These proteins are characterized by the highly conserved AIG1 domain, and in vertebrates, have been implicated in regulation of the immune system as well as apoptosis and autophagy, though their exact mechanism of action remains unclear. Recent work on cnidarian GIMAPs suggests a conserved role in immunity, apoptosis, and…
Dec 22
The specific inhibition of glycerol synthesis and the phosphorylation of a putative MAPK give insight into the mechanism of osmotic sensing in a dinoflagellate symbiont
Signaling pathways are fundamental for the establishment and maintenance of diverse symbioses. The symbiosis of cnidarians and dinoflagellate algae is the foundation for the ecological success of coral reefs, involving the transfer of photosynthetic products from symbiont to host. However, signal transduction pathways for this symbiosis remain uncharacterized. Cultured and natural cnidarian symbionts can produce glycerol, one of the main translocated photosynthates. Here, we investigate whether…
Dec 10
Isolation from a fish kill and transcriptomic characterization of Gyrodinium jinhaense off Long Island Sound
First found in Korean coastal water, the dinoflagellate Gyrodinium jinhaense is a recently established species with unclear global distribution and unexplored genomic characteristics. From a laboratory fish mortality event off Long Island Sound, USA, we isolated a dinoflagellate, and by microscopic and molecular (18S rRNA gene; >99% identical) analyses found that it resembles G. jinhaense, hence named G. jinhaense strain AP17. Towards developing a genetic database for this dinoflagellate, a…