黄唇蜾蠃蜂蜂毒的毒性特征研究

Studies on toxic characteristics of wasp venom from Rhynchium brunneum Fabricius(Hymenoptera:Eumenidae)

通过分析黄唇蜾蠃蜂蜂毒中的蛋白质组分,发现SDS-PAGE可以分离出5条主要的蛋白质带。酶活力分析显示,黄唇蜾蠃蜂蜂毒和已研究过的其他胡蜂蜂毒一样,也具有透明质酸酶和磷脂酶A的活性,但蜂毒中没有检测到酯酶、磷脂酶C和酚氧化酶活性,也不含有酚氧化酶抑制因子。由此推测,黄唇蜾蠃蜂的蜂毒仅具有较弱的过敏活性。利用寄主斜纹夜蛾幼虫进行生理学活性分析证实,体腔注射黄唇蜾蠃蜂蜂毒不能引起寄主昆虫的麻痹反应,但脑部注射一个毒腺当量的蜂毒就会引起所有受试个体产生麻痹反应,但用胰蛋白酶处理后,蜂毒即失去麻痹活性。表明:黄唇蜾蠃蜂蜂毒的麻痹活性依赖于其蛋白质组分,而活性组分的作用靶标位于寄主昆虫的中枢神经系统。

Venom is essential for parasitic wasps to paralyze and maintain their preys as suitable food for their offspring larvae. So, there must be some active components to play these roles in their venom. In our work, biochemical analysis showed that the venom from Rhynchium brunneum Fabricius contained different protein components and five main bands were resolved by SDS-PAGE. Survey on enzyme activity indicated that except for phospholipase A and hyaluronidase, no detectable activities of phospholipase C, esterase, phenoloxidase, and phenoloxidase inhibitor were found in the venom as usually expected. Physiological study showed that brain injection with the venom of one sac equivalent could make all treated larvae paralyzed. No paralytic effect was observed in the larvae treated by haemocoel injection even with 2 sac equivalents. Trypsin treatment eliminated the brain paralytic effect of venom. So, it was concluded that the venom of R. brunneum has potential allergenic activity, and its paralytic effect depends on its protein components which should act in prey＇s centre nerve system.