Isolation and preliminary characterization of proteinaceous toxins with insecticidal and antibacterial activities from black widow spider (L. tredecimguttatus) eggs.

Qian Lei,Shuai Yan,Xianchun Wang,Yizhong Yan,Xiaozhen Peng,Hai Yu,Jirong Wang

doi:10.3390/toxins7030886

Abstract

The eggs of black widow spider (L. tredecimguttatus) have been demonstrated to be rich in toxic proteinaceous components. The study on such active components is of theoretical and practical importance. In the present work, using a combination of multiple biochemical and biological strategies, we isolated and characterized the proteinaceous components from the aqueous extract of the black widow spider eggs. After gel filtration of the egg extract, the resulting main protein and peptide peaks were further fractionated by ion exchange chromatography and reversed-phase high performance liquid chromatography. Two proteinaceous components, named latroeggtoxin-III and latroeggtoxin-IV, respectively, were purified to homogeneity. Latroeggtoxin-III was demonstrated to have a molecular weight of about 36 kDa. Activity analysis indicated that latroeggtoxin-III exhibited neurotoxicity against cockroaches but had no obvious effect on mice, suggesting that it is an insect-specific toxin. Latroeggtoxin-IV, with a molecular weight of 3.6 kDa, was shown to be a broad-spectrum antibacterial peptide, showing inhibitory activity against all five species of bacteria tested, with the highest activity against Staphylococcus aureus. Finally, the implications of the proteinaceous toxins in egg protection and their potential applications were analyzed and discussed.

Highlights

The venom of spiders contains many different kinds of biologically active components including neurotoxins, many of which have been used as agent tools for neurobiological studies and as lead molecules in the development of new insecticides and pharmaceuticals [1,2,3]
We have been carrying out a systematic study on the toxicity of the black widow spider (L. tredecimguttatus) eggs and reported some related research results
All of the results demonstrate that Latroeggtoxin-IV is a peptide with a structural peculiarity, the determination of which is in progress with a combination of different techniques including partial enzymolysis and tandem mass spectrometry

Summary

Introduction

The venom of spiders contains many different kinds of biologically active components including neurotoxins, many of which have been used as agent tools for neurobiological studies and as lead molecules in the development of new insecticides and pharmaceuticals [1,2,3]. Most of the related research has been focused on the toxins in the venom of spiders, and the study of the spider toxins from outside the venom glands is limited. Different from many other venomous animals such as snakes, scorpions and some other spider species that have toxins only in the venoms secreted by their venom glands, the black widow spider has toxins in its venom glands, and throughout its body, including the legs and abdomen, and even in the eggs and the newborn spiders [4,5,6,7]. We have been carrying out a systematic study on the toxicity of the black widow spider (L. tredecimguttatus) eggs and reported some related research results. Gel electrophoresis and mass spectrometry demonstrated that the eggs are rich in high-molecular-mass proteins and peptides below

Results

Discussion

Conclusion