Publications by authors named "Linjian Ou"

Pyrene, a representative polycyclic aromatic hydrocarbon, frequently occurs in aquatic environments and is associated with lethal impacts on humans and wildlife. This study examined the impact of pyrene on , a dinoflagellate responsible for harmful algal blooms, and their capability to bioremove pyrene. In a 96 h exposure experiment, effectively reduced the pyrene concentration in seawater to 50, 100, and 200 μg/L, with a combined removal efficiency of 96% in seawater.

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Seaweed Gracilaria lemaneiformis, a significant oceanic primary producer, releases substantial dissolved organic matter (DOM) during growth and decay, potentially impacting coastal organic carbon reservoirs and microbial communities. This study aimed to investigate the bioavailability of Gracilaria-derived DOM and its interactions with microbial communities. Laboratory experiments introduced Gracilaria-derived DOM into natural seawater, tracking variations in DOM composition, microbial structure, and eight extracellular enzyme activities over 168 h.

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The recurrent brown tide phenomenon, attributed to Aureococcus anophagefferens (A. anophagefferens), constitutes a significant threat to the Qinhuangdao sea area in China, leading to pronounced ecological degradation and substantial economic losses. This study utilized machine learning and deep learning techniques to predict A.

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The increasing prevalence of phosphorus limitation in coastal waters has drawn attention to the bioavailability of cellular surface-adsorbed phosphorus (SP) as a reservoir of phosphorus in phytoplankton. This study examined the storage, utilization, and regulation of SP in the coastal waters of the East China Sea, as well as three cultivated algal bloom species (Skeletonema marinoi, Prorocentrum shikokuense, and Karenia mikimotoi) prevalent in the area. SP accounted for 14.

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Dinoflagellates, which are responsible for more than 80% of harmful algal blooms in coastal waters, are competitive in low-phosphate environments. However, the specific acclimated phosphorus strategies to adapt to phosphorus deficiency in dinoflagellates, particularly through intracellular phosphorus metabolism, remain largely unknown. Comprehensive physiological, biochemical, and transcriptomic analyses were conducted to investigate intracellular phosphorus modulation in a model dinoflagellate, Prorocentrum shikokuense, with a specific focus on membrane lipid remodeling and autophagy in response to phosphorus deficiency.

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Triazine herbicides are common contaminants in coastal waters, and they are recognized as inhibitors of photosystem II, causing significant hinderance to the growth and reproduction of phytoplankton. However, the influence of these herbicides on microalgal toxin production remains unclear. This study aimed to examine this relationship by conducting a comprehensive physiological and 4D label-free quantitative proteomic analysis on the harmful dinoflagellate Karenia mikimotoi in the presence of the triazine herbicide dipropetryn.

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Polyphosphate (polyP) has long been recognized as a crucial intracellular reservoir for phosphorus in microorganisms. However, the dynamics of polyP and its regulatory mechanism in eukaryotic phytoplankton in response to variations in external phosphorus conditions remain poorly understood. A comprehensive investigation was conducted to examine the intracellular polyP-associated metabolic response of the dinoflagellate Karenia mikimotoi, a harmful algal bloom species, through integrated physiological, biochemical, and transcriptional analyses under varying external phosphorus conditions.

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Dinoflagellates are the most common phytoplankton group and account for more than 75% of harmful algal blooms in coastal waters. In recent decades, dinoflagellates seem to prevail in phosphate-depleted waters. However, the underlying acclimation mechanisms and competitive strategies of dinoflagellates in response to phosphorus deficiency are poorly understood, especially in terms of intracellular phosphorus modulation and recycling.

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Prorocentrum donghaiense Lu (also identified as Prorocentrum shikokuense Hada and Prorocentrum obtusidens Schiller) is a bloom-forming dinoflagellate species distributed worldwide. Blooms of P. donghaiense occur annually in adjacent waters of the East China Sea (ECS), especially in the waters near the Changjiang River Estuary.

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is one of the most well-known harmful bloom species in temperate coastal waters. The present study investigated the characteristics of alkaline phosphatase (APase) and phosphodiesterase (PDEase) activities in hydrolysis of two phosphomonoesters (adenosine triphosphate (ATP) and ribulose 5-phosphate (R5P)) and a phosphodiester (cyclic adenosine monophosphate (cAMP)) in and compared its growth and physiological responses to the different forms of phosphorus substrates. produced comparable quantities of APase and PDEase to hydrolyze the organic phosphorus substrates, although hydrolysis of the phosphomonoesters was much faster than that of the phosphodiester.

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Prorocentrum obtusidens Schiller (formerly P. donghaiense Lu), a harmful algal species common in the East China Sea (ECS), often thrives with the depletion of phosphate. Three cruises in the spring of 2013 sampled an entire P.

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The nitrogen uptake kinetics and physiological growth of Karenia mikimotoi and Skeletonema costatum sensu lato grown on different N substrates and concentrations were compared in the laboratory. In the presence of three N substrates, both species preferred to take up NH. K.

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Phosphorus (P) is a potential limiting nutrient for primary production in the East China Sea (ECS). Four cruises over four seasons were conducted during 2009-2011 to evaluate the dynamics of alkaline phosphatase (AP) activity (APA) and the P status of phytoplankton in the ECS. Sampling for bulk and single-cell APA assays was performed across the ECS, which included the Changjiang River diluted water (CDW), the mid-shelf surface water (MSW), and the Kuroshio surface water (KSW) masses.

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Harmful blooms of Prorocentrum donghaiense occur annually in the phosphorus-scarce coastal waters of the East China Sea (ECS). The enzymatic activities of alkaline phosphatase (AP) and its regulation by external phosphorus were studied during a P. donghaiense bloom in this area.

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The light-harvesting protein complexes (Lhc) play key roles in the processes of light absorption and protection in diatoms. However, different Lhc protein carries out distinct function in photosynthesis. For now, roles of many Lhc proteins in light acclimation are largely unknown.

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Lu is one of the most frequently occurred harmful algae in the coastal waters of China. The growth of can be limited by nitrogen or phosphorus in marine environment. However, molecular mechanism of in response to nitrogen and phosphorus limitation is poorly understood.

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The picoplanktonic pelagophyte Aureococcus anophagefferens could trigger harmful algal blooms (HABs) to discolor water in brown, known as brown tide. Since 2009, large-scale brown tides, caused by A. anophagefferens, had been occurred in early summer for three consecutive years in the coastal waters of Qinhuangdao, China and resulted considerable deleterious effects on the scallop mariculture industry.

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Brown tides of Aureococcus anophagefferens have occurred annually in the coastal waters of Qinhuangdao since 2009. High levels of dissolved organic matter (DOM) are always measured during bloom periods. Study focusing on the effect of DOM on the occurrences of brown tides in this area is scare by far.

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Mixotrophy is found in almost all classes of phytoplankton in a wide range of aquatic habitats ranging from oligotrophic to eutrophic marine and freshwater systems. Few studies have addressed how the nutritional status of the predator and/or the prey affects mixotrophic metabolism despite the realization that mixotrophy is important ecologically. Laboratory experiments were conducted to examine changes in growth rates and physiological states of the toxic haptophyte Prymnesium parvum when fed Rhodomonas salina of varying nutritional status.

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Colony enlargement in Phaeocystis globosa has been considered as an induced defense strategy that reduces its susceptibility to grazers, but allocation costs inflicted by this plastic morphological defense are poorly understood. We conducted experiments in which P. globosa cultures were exposed to chemical cues from copepods, ciliates and heterotrophic dinoflagellates, respectively, under nutrient sufficient and deficient conditions to evaluate allocation costs associated with induced defense.

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The bioavailability of dissolved organic phosphorus (DOP) compounds to harmful alga Prorocentrum donghaiense Lu and its alkaline phosphatase activity (APA) were studied. Results showed that P. donghaiense could utilize the test DOP compounds such as glucose-6-phosphate (G-6-P), adenosine triphosphate (ATP) and ribonucleic acid (RNA) to sustain its growth.

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Ectoenzymes play an important role in the material cycle and energy conversion in aquatic ecosystem. The researches of ectoenzyme are of significance in further understanding the marine carbon biogeochemical cycle and the countermeasures of algae under bloom conditions. In this paper, the research methods, characteristic activity and size distribution, controlling factors and their ecological significances of algal ectoenzymes were reviewed, and ectoenzyme introduced as one kind of new trophic state index.

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