Spectroscopic, structural and functional characterization of Intrinsically Disordered Protein DHN1 from Zea mays

Abstract

"Intrinsically Disordered proteins (IDPs) emerged as an essential class of proteins in the past two decades due to their functional relevance without having a proper 3-dimensional structure. Here, we investigated dehydrin (DHN1) protein from Zea mays, an IDP that belongs to the Late Embryogenesis Abundant (LEA) protein family. This thesis work focused on studying DHN1 structural dynamics and functional role using the novel spectroscopic tool Protein Charge Transfer Spectroscopy (ProCharTS) and other spectroscopic techniques like UV-visible and fluorescence spectroscopy. To investigate the structural change and functional role of DHN1, two mutants: DHN1 CW1 (Trp122 −Cys62) and DHN1 W3 (Trp3), were generated using sitedirected mutagenesis. The structural analysis of the DHN1 protein divulges its complete random coil conformation in the native state. ProCharTS absorption was found to be sensitive to the conformational changes in DHN1 induced by the changes in pH and temperature of aqueous medium. Next, we investigated the luminescence characteristic of this novel ProCharTS in the DHN1 protein. This study suggests that ProCharTS in DHN1 protein is luminescent in nature. We found that the observed luminescence is excitation wavelength dependent and possesses a significant presence in the UV-Visible region. ProCharTS luminescence has a low quantum yield and lower luminescence lifetime. The origin behind this luminescence could be charge"