The Xiamen Symposium on Marine Environmental Sciences (XMAS 2025)

The requirement of zinc by Amphidinium carterae, a prevalent benthic dinoflagellate known for producing hemolytic polyketides in coastal marine environment, remains poorly evaluated. We performed a cultural experiment to determine the influence of zinc on the growth, photosynthesis, and polyketide biosynthesis of the Amphidinium carterae under total zinc concentrations from 0 to ~8.0 × 10^-5 M. Our preliminary results demonstrate that the decreasing zinc concentration is accompanied by a gradually decreasing photosynthesis efficiency of A. cartera, which is inferred from smaller PSII cross-section area and lower chlorophyll a contents. As Zn is an essential element for regulating the transcription, translation, and protein-protein interactions in phytoplankton, its availability may also affect the biosynthetic activity of polyketides in the species and thus their toxic level to marine fish species. Therefore, an erythrocyte lysis assay is being conducted to quantitatively determine the amount of polyketide produced under different zinc bioavailability levels. Our study could unravel mechanistically the influences of Zn on A carterae growth, photosynthesis, and polyketides production, and facilitate the evaluation of how Zn availability modulates the bloom and toxicity of harmful algae in coastal oceans.
 

Zinc,Harmful Algae Bloom,Dinoflagellates,Polyketide Biosynthesis