Details

Autor(en) / Beteiligte

• Wen, Yingjie
• Jiang, Xunyuan
• Yang, Chen
• Meng, Huayue
• Wang, Binfeng
• Wu, Hanxiang
• Zhang, Zhixiang
• Xu, Hanhong

Titel

The linker length of glucose–fipronil conjugates has a major effect on the rate of bioactivation by β‐glucosidase

Ist Teil von

• Pest management science, 2019-03, Vol.75 (3), p.708-717

Ort / Verlag

Chichester, UK: John Wiley & Sons, Ltd

Erscheinungsjahr

2019

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• BACKGROUND Endogenous plant β‐glucosidases can be utilized to hydrolyze pro‐pesticides and release the bioactive pesticide. Two related glucose–fipronil conjugates with different linkers structure, N‐{3‐cyano‐1‐[2,6‐dichloro‐4‐(trifluoromethyl) phenyl]‐4‐[(trifluoromethyl) sulfinyl]‐1H‐pyrazol‐5‐yl}‐1‐(2‐triazolethyl‐β‐d‐glucopyranoside)‐1H‐1,2,3‐triazole‐4‐methanamine (GOTF) and N‐{3‐cyano‐1‐[2,6‐dichloro‐4‐(trifluoromethyl) phenyl]‐4‐[(trifluoromethyl)‐sulfinyl]‐1H‐pyrazol‐5‐yl}‐2‐aminoethyl‐β‐d‐glucopyranoside (GOF), were deglucolysated by β‐glucosidase both in vitro and in vivo at different rates. Here, the basis for these differences was investigated by revealing the kinetics of the reaction and by modeling molecular docking between enzyme and substrate. RESULTS Results from kinetic study showed that the reaction rate was the main reason for the poorer rate of GOF hydrolysis with respect to GOTF. Modeling of substrate docking indicated that the spacer arm of glucose–fipronil conjugates affects the strength of non‐covalent bonds within the active site and the position of fipronil within the pocket. Four glucose–fipronil conjugates and four corresponding aglycones were synthesized, and the hydrolysis data confirmed that the increased tether length between the bulky aglycone and glycone would lead to faster hydrolysis rate. The bioassay results indicated that most glucose–fipronil conjugates displayed moderate to excellent insecticidal activities in vivo against Plutella xylostella larvae. CONCLUSION This study provides a potential strategy to optimize the substrate structure to enhance hydrolytic specificity in order to design appropriate phloem mobile pro‐pesticides. © 2018 Society of Chemical Industry Plant endogenous β‐glucosidases can interact with exogenously applied pro‐pesticides to release a bioactive form of the pesticide. The study investigates the structure–activity relationship between the glucose–fipronil conjugates and β‐glucosidase.