Structural investigation of the male European Corn Borer's pheromone binding protein-3

Abstract

European Corn Borer (Ostrinia nubilalis) is an economically impacting moth of the North American agricultural community. First introduced to the United States in 1917, Ostrinia nubilalis now causes a yearly sum of approximately $1 billion in lost crops. The most effective method of ending the losses due to O. nubilalis lie in blocking the reproduction process of the sexually mature moths. By targeting and inhibiting male O. nubilalis pheromone detection system via sensory inhibition, the life cycle of the moth can be disrupted resulting in a decrease of the O. nubilalis population. O. nubilalis pheromone-binging protein 3 (OnubPBP3) plays a critical role in pheromone detection by the male moth. Understanding the mechanism of pheromone detection and the role of OnubPBP3 in this process, structure, and function of this protein, and its interaction with pheromones is critical for developing an inhibitor. We present here the transformation, overexpression, refolding of the inclusion bodies, purification and the preliminary biophysical analysis of OnubPBP3 through fluorescence spectroscopy, circular dichroism (CD) analysis, and 2D {1H, 15N} heteronuclear single quantum coherence (HSQC) NMR spectroscopy. The data gained suggest that OnubPBP3 is a globular protein, primarily helical, and contains a hydrophobic binding pocket where it is believed to interact with the pheromone.