海洋多肽CTx-btg01的制备及其杀虫活性研究

The preparation and insecticidal activity of marine peptide CTx-btg01

目的合成海洋多肽CTx-btg01研究其杀虫活性。方法采用多肽固相合成法(SPPS)合成线性肽CTx-btg01,利用两步法氧化折叠线性肽后质谱鉴定和高效液相色谱(HPLC)纯化,再利用MTT法、昆虫注射法和电生理实验研究其杀虫活性。结果采用SPPS法成功地合成了CTx-btg01,其纯度>95%;MTT实验表明CTx-btg01能抑制昆虫细胞sf9的生长,其半数有效量为0.16 nmol/L;昆虫注射法实验表明CTx-btg01能够有效的杀死黄粉虫,半数致死剂量为0.55μg/mg;电生理实验结果表明10μmol/L CTx-btg01对鼠源乙酰胆碱α2β3无阻断活性,对α3β4具有较弱的阻断活性。结论海洋多肽CTx-btg01具有良好的抑制昆虫细胞生长,高效的杀虫活性和较弱的哺乳动物毒性作用,可为研发新型、安全和高效的多肽类生物杀虫剂奠定基础。

Objective Marine peptide CTx-btg01 was synthesized to study its insecticidal activity. Methods CTx-btg01 was synthesized by solid phase peptide synthesis(SPPS). The two-step oxidation-folding linear peptide was identified by mass spectrometry and purified by high performance liquid chromatography(HPLC). The insecticidal activity of CTx-btg01 was evaluated by the MTT method, the insect injection method, and electrophysiology method. Results CTx-btg01 was successfully synthesized by SPPS method, and its purity is more than 95%. The activity test showed CTx-btg01 could inhibit the growth of sf9 in insect cells, and the half effective dose was 0.16 nmol/L. It had a killing effect on meal-worms, with a median lethal dose being 0.55 μg/mg. Electrophysiological experiments showed that CTx-btg01 had no blocking activity on rat-derived acetylcholine receptor α2β3 and had weak blocking activity on α3β4. Conclusion Peptide CTx-btg01 has good inhibition of insect cell growth, high insecticidal activity and weak toxicity to mammals, which can lay the foundation for the development of new, safe and efficient peptide biological insecticides.