Ostrinia furnacalis PBP2 solution NMR structure: Insight into ligand binding and release mechanisms
Ostrinia furnacalis PBP2 solution NMR structure: Insight into ligand binding and release mechanisms
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DOI：
10.1002/pro.4438
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发表时间：
2022-09
期刊：
影响因子：
8
通讯作者：
S. R. Dahal;Jacob L Lewellen;Shine Ayyappan;B. Chaudhary;Viswanath Nukala;Smita Mohanty
中科院分区：
文献类型：
--
作者：
S. R. Dahal;Jacob L Lewellen;Shine Ayyappan;B. Chaudhary;Viswanath Nukala;Smita Mohanty
玉米螟是一种入侵性鳞翅目农业害虫，依靠嗅觉进行交配和繁殖。雄蛾有一个非常敏感的嗅觉系统，可以探测到雌蛾在很远的地方散发的性信息素。雄蛾触角中的信息素结合蛋白在嗅觉神经元树突膜上信息素的摄取、运输和释放中起关键作用。在这里，我们报告了第一个高分辨率NMR结构的信息素结合蛋白质从鸵鸟物种在pH 6.5。Ostriniaperacalis PBP 2（OfurPBP 2）的核心由六个螺旋组成，α1a（2-14），α1b（16-22），α2（27-37），α3（46-60），α4（70-80），α5（84-100）和α6（107-124）围绕一个大的疏水口袋。其结构由三个二硫键19-54、50-108和97-117稳定。与其他鳞翅目PBP的非结构化C末端相反，OfurPBP 2的C末端在pH 6.5下折叠成α螺旋（α7）。该蛋白质对两种信息素异构体都具有纳摩尔亲和力。两种信息素，E-12和Z-12-十四碳烯乙酸酯与OfurPBP 2的分子对接显示，残基Met 5，Lys 6，Met 8，Thr 9，Phe 12，Phe 36，Trp 37，Phe 76，Ser 115，Phe 118，Lys 119，Ile 122，His 123和Ala 128与两种异构体相互作用，而Thr 9与乙酸酯头基形成氢键。NMR结构和热展开与CD的研究表明，在pH 4.5的配体释放可能是由于部分展开的蛋白质。
Ostrinia furnacalis is an invasive lepidopteran agricultural pest that relies on olfaction for mating and reproduction. Male moths have an extremely sensitive olfactory system that can detect the sex pheromones emitted by females over a great distance. Pheromone‐binding proteins present in the male moth antenna play a key role in the pheromone uptake, transport, and release at the dendritic membrane of the olfactory neuron. Here, we report the first high‐resolution NMR structure of a pheromone‐binding protein from an Ostrinia species at pH 6.5. The core of the Ostrinia furnacalis PBP2 (OfurPBP2) consists of six helices, α1a (2–14), α1b (16–22), α2 (27–37), α3 (46–60), α4 (70–80), α5 (84–100), and α6 (107–124) surrounding a large hydrophobic pocket. The structure is stabilized by three disulfide bridges, 19–54, 50–108, and 97–117. In contrast to the unstructured C‐terminus of other lepidopteran PBPs, the C‐terminus of OfurPBP2 folds into an α‐helix (α7) at pH 6.5. The protein has nanomolar affinity towards both pheromone isomers. Molecular docking of both pheromones, E‐12 and Z‐12‐tetradecenyl acetate, to OfurPBP2 revealed that the residues Met5, Lys6, Met8, Thr9, Phe12, Phe36, Trp37, Phe76, Ser115, Phe118, Lys119, Ile122, His123, and Ala128 interact with both isomers, while Thr9 formed a hydrogen bond with the acetate head group. NMR structure and thermal unfolding studies with CD suggest that ligand release at pH 4.5 is likely due to the partial unfolding of the protein.