Research on siderophore secreted by Prorocentrum donghaiense Lu under iron-limited conditions
铁限制条件下东海原甲藻分泌铁载体

Under iron-limited conditions,marine microorganisms are able to secrete low-molecular-weight,highly specific iron chelators termed siderophores.These compounds scavenge iron from protein complexes or insoluble hydroxides in the extracellular environment and transport it to the cell cytosol via a membrane-bound receptor protein in the microorganism.Iron is a necessary requirement in marine ecosystems.Therefore research on siderophores is very significant to interpretation of high nitrate low chlorophyll(HNLC) regions and iron hypothesis.However,it is not clear whether eukaryotic phytoplankton can produce the iron-specific chelating compounds.Therefore,a systematic investigation was carried out for siderophore secreted by P.donghaiense Lu under iron-limited conditions.Parameters studied included the growth of the algae in iron-added and iron-deficient medium,the secretion of siderophore during algae growth,and the effect of algae population inoculated on the siderophore production.Results showed that the algae growth rate in iron-deficient medium was slower than those in iron-rich medium.Under iron-limited conditions,the siderophore production increased along with algae growth.Maximum production was observed in the exponential growth period.Thereafter the rate of algae growth and siderophore secretion started to decrease.Furthermore,increasing algae populationt resulted in secreting more siderophore and shortening the time needed to reach maximum production.