Siderophore mediated attenuation of cadmium toxicity by paddy field cyanobacterium Anabaena oryzae

The efficacy of dihydroxamate siderophore in attenuation/mitigation of cadmium toxicity, an optimum level of cadmium under which cyanobacterium can grow and produce siderophore, complexation behaviour of cadmium and siderophore and kinetics of complexation along with in silico analysis have been investigated in paddy field cyanobacterium Anabaena oryzae under iron replete and deplete conditions. Results showed that cadmium concentration as 1.0 μM is optimum for growth as well as siderophore production in iron replete and deplete culture conditions. The complexation between cadmium-siderophore was evident in spectral scan. Kinetic studies as well as in silico docking analysis indicate that like iron, cadmium also forms a thermodynamically stable complex with siderophore. Thus our results suggest that the siderophore produced by Anabaena oryzae can act as a biological sequestering agent for the mitigation of cadmium metal ions from the paddy fields to improve crop productivity.