A Spectroscopic Approach towards the Comparative Binding Studies of the Antioxidizing Flavonol Myricetin with Various Single‐Stranded RNA

Abstract

RNA based drugs have come to limelight owing to the major role played by RNA in the development of many viral diseases. Molecules which can effectively bind with RNA can induce morphological changes in RNA which further modifies its biological properties. Flavonoids are phytochemicals having a wide range of pharmacological properties and are known to interact with DNA. We have used RNA instead of DNA and aimed at establishing a comparison of binding of three single stranded forms of RNA homopolymers namely polyriboadenylic acid [poly(rA)], polyuridylic acid [poly(rU)] and polycytidylic acid [poly(rC)] with the flavonol myricetin (herein after MTN), our probe of interest. A series of spectroscopic experiments like spectrophotometry, spectrofluorimetry and circular dichroism studies indicate a stronger binding of myricetin with poly(rA) followed by poly(rU) and finally poly(rC). This was confirmed from the construction of Scatchard plot using the Mc‐Ghee von Hippel equation for cooperative binding. The magnitude of the order of binding was 103 M−1 at 25 °C in all the cases. It is to be noted that most eukaryotic mRNAs have a poly adenylate tail. Binding of MTN to poly(rA) in virulent cells could effectively alter the encoded protein synthesis and reduce chances of occurrence of the disease.