| Title: | Optimization of reverse chemical ecology method: false positive binding of Aenasius bambawalei odorant binding protein 1 caused by uncertain binding mechanism |
| Author(s): | Li QL; Yi SC; Li DZ; Nie XP; Li SQ; Wang MQ; Zhou AM; |
| Address: | "Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China" |
| ISSN/ISBN: | 1365-2583 (Electronic) 0962-1075 (Linking) |
| Abstract: | "Odorant binding proteins (OBPs) are considered as the core molecular targets in reverse chemical ecology, which is a convenient and efficient method by which to screen potential semiochemicals. Herein, we identified a classic OBP, AbamOBP1 from Aenasius bambawalei, which showed high mRNA expression in male antennae. Fluorescence competitive binding assay (FCBA) results demonstrated that AbamOBP1 has higher binding affinity with ligands at acid pH, suggesting the physiologically inconsistent binding affinity of this protein. Amongst the four compounds with the highest binding affinities at acid pH, 2, 4, 4-trimethyl-2-pentene and 1-octen-3-one were shown to have attractant activity for male adults, whereas (-)-limonene and an analogue of 1-octen-3-ol exhibited nonbehavioural activity. Further homology modelling and fluorescence quenching experiments demonstrated that the stoichiometry of the binding of this protein to these ligands was not 1: 1, suggesting that the results of FCBA were false. In contrast, the apparent association constants (Ka) of fluorescence quenching experiments seemed to be more reliable, because 2, 4, 4-trimethyl-2-pentene and 1-octen-3-one had observably higher Ka than (-)-limonene and 1-octen-3-ol at neutral pH. Based on the characteristics of different OBPs, various approaches should be applied to study their binding affinities with ligands, which could modify and complement the results of FCBA and contribute to the application of reverse chemical ecology" |
| Keywords: | "Amino Acid Sequence Animals Fluorescence Insect Proteins/chemistry/*genetics/metabolism Models, Genetic Molecular Docking Simulation Receptors, Odorant/chemistry/*genetics/metabolism Sequence Alignment Sequence Homology, Amino Acid Wasps/*genetics/metabol;" |
| Notes: | "MedlineLi, Q L Yi, S C Li, D Z Nie, X P Li, S Q Wang, M-Q Zhou, A M eng Research Support, Non-U.S. Gov't England 2018/01/31 Insect Mol Biol. 2018 Jun; 27(3):305-318. doi: 10.1111/imb.12372. Epub 2018 Jan 30" |
