Marine Actinomycetes Siderophores: Types, High Throughput Characterization Techniques, Applications, and Their Association with Nanotechnology: A Comprehensive Review

Iron is one of the most essential micronutrients for all the existing life systems. However, at biological pH, iron gets oxidised to insoluble oxyhydroxide polymers. In low iron conditions, microbes secrete specialised molecules called siderophores, which are high affinity and low molecular weight chelating agents that increase the availability of iron for microbial usage. In marine water, concentration of iron is as low as nanomolar. Very less light has been shed on the sidero-phores of marine actinomycetes. Actinomycetes are known for producing novel secondary metabolites with diverse biological activities, siderophores are one such bioactive metabolite. Siderophores significantly differs in structure based on the ligands of oxygen for iron(III) (Ferric, Fe +3 ) synchronization. The applications of siderophores include heavy metal remediation, treating metal toxicity. In medical field, they are employed to treat diseases like thalassemia, sickle cell anaemia, and used to treat few cancers. They are being exploited to combat antibiotic-resistant bacteria, which is a mounting problem these days. It has been reported that they can also be used as biosensors for iron detection. Recently developed high throughput strategies, HPLC-MS and MS/MS methods are used to identify and quantify many unknown siderophores. In this review, recent developments, and diverse applications of marine siderophores are reported. The review also highlights the association and involvement of siderophores in the synthesis of various NPs and their applications in the fields of medical to environmental biotechnology.