The identity of Centrodinium elongatum, type species of the dinoflagellate genus Centrodinium (Dinophyceae), and a review on the synonymy of allied species.

The planktonic dinoflagellate genus Centrodinium has been understudied, with the type species C. elongatum remaining undocumented since the original description. Here, we report C.

A decade of dinoflagellate genomics illuminating an enigmatic eukaryote cell.

Dinoflagellates are a remarkable group of protists, not only for their association with harmful algal blooms and coral reefs but also for their numerous characteristics deviating from the rules of eukaryotic biology. Genome research on dinoflagellates has lagged due to their immense genome sizes in most species (~ 1-250 Gbp). Nevertheless, the last decade marked a fruitful era of dinoflagellate genomics, with 27 genomes sequenced and many insights attained.

Higher genotypic diversity and distinct assembly mechanism of free-living Symbiodiniaceae assemblages than sympatric coral-endosymbiotic assemblages in a tropical coral reef.

While Symbiodiniaceae dinoflagellates are essential for coral health, ambient free-living counterparts are crucial for coral recruitment and resilience. Comparing free-living and Symbiodiniaceae communities can potentially provide insights into endosymbiont acquisition and recurrent recruitment in bleaching recovery. In this study, we studied coral-endosymbiotic and ambient free-living Symbiodiniaceae communities in the South China Sea.

Phosphorus limitation intensifies heat-stress effects on the potential mutualistic capacity in the coral-derived Symbiodinium.

Coral reef ecosystems have been severely ravaged by global warming and eutrophication. Eutrophication often originates from nitrogen (N) overloading that creates stoichiometric phosphorus (P) limitation, which can be aggravated by sea surface temperature rises that enhances stratification. However, how P-limitation interacts with thermal stress to impact coral-Symbiodiniaceae mutualism is poorly understood and underexplored.

Salinity decline promotes growth and harmful blooms of a toxic alga by diverting carbon flow.

Global climate change intensifies the water cycle and makes freshest waters become fresher and vice-versa. But how this change impacts phytoplankton in coastal, particularly harmful algal blooms (HABs), remains poorly understood. Here, we monitored a coastal bay for a decade and found a significant correlation between salinity decline and the increase of Karenia mikimotoi blooms.

Succession of diversity, assembly mechanisms, and activities of the microeukaryotic community throughout Scrippsiella acuminata (Dinophyceae) bloom phases.

Harmful algal bloom (HAB) is a rapidly expanding marine ecological hazard. Although numerous studies have been carried out about the ecological impact and the ecological mechanism of HAB outbreaks, few studies have comprehensively addressed the shifts of species composition, metabolic activity level, driving factors and community assembly mechanisms of microeukaryotic plankton in the course of the bloom event. To fill the gap of research, we conducted 18S ribosomal DNA and RNA sequencing during the initiation, development, sustenance and decline stages of a Scrippsiella acuminata (S.

Shining light on dinoflagellate photosystem I.

Dinoflagellates are ecologically important and essential to corals and other cnidarians as phytosymbionts, but their photosystems had been underexplored. Recently, photosystem I (PSI) of dinoflagellate sp. was structurally characterized using cryo-Electron Microscopy (cryo-EM).

Dinoflagellate Proton-Pump Rhodopsin Genes in Long Island Sound: Diversity and Spatiotemporal Distribution.

Microbial proton-pump rhodopsin (PPR)-based phototrophy, a light-harvesting mechanism different from chlorophyll-based photosystems, may contribute significantly to solar energy entry into the marine ecosystem. PPR transforms solar energy into cellular energy that is used for various metabolic processes in the cells or flagellar movement. Although rhodopsins or their encoding genes have been documented in a wide phylogenetic range of cultured dinoflagellates, information is limited about how widespread and how spatiotemporally dynamical dinoflagellate PPR (DiPPR) are in natural marine ecosystems.

community transcriptomics illuminates CO-fixation potentials and supporting roles of phagotrophy and proton pump in plankton in a subtropical marginal sea.

Lineage-wise physiological activities of plankton communities in the ocean are important but challenging to characterize. Here, we conducted whole-assemblage metatranscriptomic profiling at continental shelf and slope sites in the South China Sea to investigate carbon fixation potential in different lineages. expression, the proxy of Calvin carbon fixation (CCF) potential, was mainly contributed by Bacillariophyta, Chlorophyta, Cyanobacteria, and Haptophyta, which was differentially affected by environmental factors among lineages.

Effects and mechanisms of glyphosate as phosphorus nutrient on element stoichiometry and metabolism in the diatom .

The ability to utilize dissolved organic phosphorus (DOP) gives phytoplankton competitive advantages in P-limited environments. Our previous research indicates that the diatom could grow on glyphosate, a DOP with carbon-phosphorus (C-P) bond and an herbicide, as sole P source. However, direct evidence and mechanism of glyphosate utilization are still lacking.

Clustered Regularly Interspaced Short Palindromic Repeat/CRISPR-Associated Protein and Its Utility All at Sea: Status, Challenges, and Prospects.

Initially discovered over 35 years ago in the bacterium as a defense system against invasion of viral (or other exogenous) DNA into the genome, CRISPR/Cas has ushered in a new era of functional genetics and served as a versatile genetic tool in all branches of life science. CRISPR/Cas has revolutionized the methodology of gene knockout with simplicity and rapidity, but it is also powerful for gene knock-in and gene modification. In the field of marine biology and ecology, this tool has been instrumental in the functional characterization of 'dark' genes and the documentation of the functional differentiation of gene paralogs.

Glyphosate (Roundup) as phosphorus nutrient enhances carbon and nitrogen accumulation and up-regulates phosphorus metabolisms in the haptophyte Isochrysis galbana.

Inorganic phosphate limitation for phytoplankton may be intensified with water stratification by global warming, and with the increasing nitrogen: phosphorus (N:P) ratio in coastal zones resulting from continuous anthropogenic N overloading. Under these circumstances, phytoplankton's ability to use dissolved organic phosphorus (DOP) will give species a competitive advantage. In our previous study, we have shown that the haptophyte Isochrysis galbana can use glyphosate (Roundup) as a P nutrient source to support growth, but the mechanism of how remains unexplored.

Alkaline Phosphatase PhoD Mutation Induces Fatty Acid and Long-Chain Polyunsaturated Fatty Acid (LC-PUFA)-Bound Phospholipid Production in the Model Diatom .

With rapid growth and high lipid contents, microalgae have become promising environmentally friendly candidates for renewable biodiesel and health supplements in our era of global warming and energy depletion. Various pathways have been explored to enhance algal lipid production, especially gene editing. Previously, we found that the functional loss of PhoD-type alkaline phosphatase (AP), a phosphorus-stress indicator in phytoplankton, could lead to increased lipid contents in the model diatom , but how the AP mutation may change lipid composition remains unexplored.

A grazing-driven positive nutrient feedback loop and active sexual reproduction underpin widespread Noctiluca green tides.

The mixoplankton green Noctiluca scintillans (gNoctiluca) is known to form extensive green tides in tropical coastal ecosystems prone to eutrophication. In the Arabian Sea, their recent appearance and annual recurrence have upended an ecosystem that was once exclusively dominated by diatoms. Despite evidence of strong links to eutrophication, hypoxia and warming, the mechanisms underlying outbreaks of this mixoplanktonic dinoflagellate remain uncertain.

Active viral infection during blooms of a dinoflagellate indicates dinoflagellate-viral co-adaptation.

This study represents the first that investigates virus infection in dinoflagellate blooms. Our findings reveal highly similar viral assemblages that infected the bloom species and a co-adapted metabolic relationship between the host and the viruses in the blooms, which varied between the prolonged and the short-lived blooms of the same dinoflagellate species. These findings fill the gap in knowledge regarding the identity and behavior of viruses in a dinoflagellate bloom and shed light on what appears to be the complex mode of infection.

Species-dependent effects of seawater acidification on alkaline phosphatase activity in dinoflagellates.

Increases of atmospheric CO cause ocean acidification (OA) and global warming, the latter of which can stratify the water column and impede nutrient supply from deep water. Phosphorus (P) is an essential nutrient for phytoplankton to grow. While dissolved inorganic phosphorus (DIP) is the preferred form of P, phytoplankton have evolved alkaline phosphatase (AP) to utilize dissolved organic phosphorus (DOP) when DIP is deficient.

Phosphorus nutrition strategies in a Symbiodiniacean species: Implications in coral-alga symbiosis facing increasing phosphorus deficiency in future warmer oceans.

Coral reefs thrive in the oligotrophic ocean and rely on symbiotic algae to acquire nutrients. Global warming is projected to intensify surface ocean nutrient deficiency and anthropogenic discharge of wastes with high nitrogen (N): phosphorus (P) ratios can exacerbate P nutrient limitation. However, our understanding on how symbiotic algae cope with P deficiency is limited.

Two-sided effects of the organic phosphorus phytate on a globally important marine coccolithophorid phytoplankton.

Dissolved organic phosphorus (DOP) is a potential source of aquatic eutrophication and pollution because it can potentially stimulate growth in some species and inhibit growth in other species of algae, the foundation of the marine ecosystem. Inositol hexaphosphate (also named phytic acid or PA), an abundant organophosphate, is presumably ubiquitous in the marine environment, but how it affects marine primary producers is poorly understood. Here, we investigated the bioavailability of this DOP to the cosmopolitan coccolithophore .

Role of diatom-derived oxylipins in organic phosphorus recycling during coastal diatom blooms in the northern South China Sea.

Diatom-bacteria interactions and the associated bloom dynamics have not been fully understood in the coastal oceans. Here, we focus on the polyunsaturated aldehydes (PUAs) produced by diatoms in the post-bloom phase and look into their roles in microbial phosphorus (P) recycling outside of a P-limited estuary. The phytoplankton community in the bloom was dominated by PUAs-producing diatoms (Skeletonema costatum, Thalassiosira spp.

A comparative study reveals the relative importance of prokaryotic and eukaryotic proton pump rhodopsins in a subtropical marginal sea.

Proton-pump rhodopsin (PPR) in marine microbes can convert solar energy to bioavailable chemical energy. Whereas bacterial PPR has been extensively studied, counterparts in microeukaryotes are less explored, and the relative importance of the two groups is poorly understood. Here, we sequenced whole-assemblage metatranscriptomes and investigated the diversity and expression dynamics of PPR in microbial eukaryotes and prokaryotes at a continental shelf and a slope site in the northern South China Sea.

Phosphate limitation and ocean acidification co-shape phytoplankton physiology and community structure.

A new study reports synergistic inhibitory effects of ocean acidification and phosphate limitation on the nitrogen-fixing capacity of a globally important cyanobacterium species. Inspired by the report, this Comment presents the complexity of how ocean acidification and phosphate limitation affect phytoplankton physiologies and species beyond nitrogen fixation and cyanobacteria, and what future research is needed to address the remaining crucial questions.

Molecular Ecological Analyses Illuminate Distinct Factors Regulating Formation and Demise of a Harmful Dinoflagellate Bloom.

The development and demise of a harmful algal bloom (HAB) are generally regulated by multiple processes; identifying specific critical drivers for a specific bloom is important yet challenging. Here, we conducted a whole-assemblage molecular ecological study on a dinoflagellate bloom to address the hypothesis that energy and nutrient acquisition, defense against grazing and microbial attacks, and sexual reproduction are critical to the rise and demise of the bloom. Microscopic and molecular analyses identified the bloom-causing species as and showed that the ciliate sp.