From structure to function: Recombinant expression, purification and structural characterization of Ostrinia nubilalis pheromone binding protein 2

European corn borer (ECB) Ostrinia nubilalis (Onub), is a profoundly serious pest of corn, sweet corn, and other crops. ECB accounts for 5.5 to 8.5 million tons of corn loss in an average year in Europe and other countries. ECB was introduced to United States in the 1900s. This pest accounts for 20% of yield loss in North America, with damages estimated to exceed US $1 billion annually. Pesticides and insecticides used to control these pests cause harmful effects in the environment. Moreover, pests show resistance to it. Thus, there is an urgent need for an alternative method for control of this pest. Mating in lepidopteran moths, such as Ostrinia nubilalis is initiated with the detection of female-secreted pheromones by the males. The pheromone binding proteins (PBPs) present in the male moth antenna play a critical role in pheromone detection. Of the five PBPs identified in Ostrinia nubilalis, OnubPBP2 and OnubPBP3 have male-biased expression. An alternate approach for pest control is to target the mating process by intervening in the pheromone detection system of the male moth. A Structure-function study of the OnubPBP2 is critical to interfere in the pheromone detection system of this invasive insect pest in a species-specific and environmentally friendly manner. To achieve this goal, we have cloned, expressed, purified, and investigated the recombinant OnubPBP2 through biophysical characterization. We have determined the high-resolution three-dimensional structure of OnubPBP2 by NMR spectroscopy.