抑制剂胱氨酸结多肽的抗菌和杀虫活性及进化

Antimicrobial and insecticidal activities and evolution of inhibitor cystine knot peptides

抑制剂胱氨酸结(inhibitor cystine knot, ICK)多肽是胱氨酸结(cystine knot, CK)多肽的三大家族成员之一。这种类型的多肽含有反向平行的3个β折叠,由3对二硫键形成稳定的拓扑学打结。它们广泛地分布在动物、植物、真菌甚至原核生物中,具有蛋白酶抑制剂,离子通道毒素以及抗微生物、抗疟疾及抗病毒活性等多种生物学功能。本文首先总结了昆虫中已发现的抗微生物活性和离子通道毒素活性的ICK肽;然后介绍了有毒动物尤其是蜘蛛、蝎子,以及植物中一些神经毒素活性的ICK肽,它们通常靶向昆虫体内的各种离子通道,从而发挥杀虫效果;最后结合ICK肽的基因序列特征,结构域和二硫键数目以及物种分布,对其进化多样性进行了探讨。

Inhibitor cystine knot(ICK)peptides are one of the three family members of cystine knot(CK)peptides.Peptides of this kind consist of a triplet-stranded antiparallelβ-sheet stabilized by three disulfide bonds to form a topological knot.They are widely distributed in animals,plants,fungi and even prokaryotes,exhibiting a diversity of biological functions including protease inhibitors,ion channel toxins,and antimicrobial,antimalarial and antiviral activities.In this article,we firstly summarized the ICK peptides found in insects with antimicrobial and ion channel toxin activities,and then introduced some neurotoxic ICK peptides in poisonous animals especially spiders and scorpions,as well as plants.These toxins usually target various ion channels of insects to exert their insecticidal activity.Finally,we discussed the evolutionary diversity of ICK peptides in combination with their gene sequence characteristics,the numbers of their domains and disulfide bonds and species distribution.