Ostrinia nubilalis, a lepidopteran moth, also known as the European corn borer, has a major impact on the production of economically important crops in the United States and Europe. The female moth invites the male moth for mating through the release of pheromones, a volatile chemical signal. Pheromone binding proteins (PBPs) present in the male moth antennae are believed to pick up the pheromones, transport them across the aqueous sensillum lymph, and deliver them to the olfactory receptor neurons. Here we report for the first time the cloning, expression, refolding, purification, and structural characterization of Ostrinia nubilalis PBP3 (OnubPBP3). The recombinant protein showed nanomolar affinity to each isomer of the Ostrinia pheromones, E- and Z-11-tetradecenyl acetate. In a pH titration study by nuclear magnetic resonance, the protein exhibited an acid-induced unfolding at pH below 5.5. The molecular dynamics simulation study demonstrated ligand-induced conformational changes in the protein with both E- and Z-isomers of the Ostrinia pheromone. The simulation studies showed that while protein flexibility decreases upon binding to E-pheromone, it increases when bound to Z-pheromone. This finding suggests that the OnubPBP3 complex with E-pheromone is more stable than with Z-pheromone.
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1H, 13C, and 15N resonance assignment and secondary structure of the pheromone binding protein from the agricultural pest Ostrinia furnacalis (OfurPBP2)
Ostrinia furnacalis, a lepidopteran moth, is an invasive pest found in Asia, Australia, Africa and parts of the United States. The Ostrinia furnacalis pheromone-binding protein2 (OfurPBP2), present in the male moth antenna, plays a role in the detection of female-secreted pheromone in a process that leads to mating. To understand the structural mechanism of pheromone binding and release in this pest, we have initiated characterization of OfurPBP2 by solution NMR. Here, we report the backbone resonance assignments and the secondary structural elements of OfurPBP2 at pH 6.5 using uniformly 13C, 15N-labeled protein with various triple resonance NMR experiments. The assignments are 97 % completed for backbone and 88 % completed for side-chain resonances. The secondary structure of OfurPBP2, based on backbone chemical shifts, consists of eight α-helices, including a well-structured C-terminal helix.
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- Award ID(s):
- 1807722
- PAR ID:
- 10159529
- Date Published:
- Journal Name:
- Biomolecular NMR assignments
- ISSN:
- 1874-2718
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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