Биохимия и аналитическая биохимия

Абстрактный

Stabilization of Clostridium botulinum Toxin Complex Using Chemical Crosslinkers

Ajay K. Singh, David Hodge and Shashi K. Sharma*

Clostridium botulinum produces seven antigenically-distinct botulinum neurotoxins (BoNTs) which cause severe neuroparalytic illness botulism in humans and animals. In bacterial cultures, secreted BoNTs are associated with several neurotoxin-associated proteins (NAPs) forming toxin complexes (TCs). NAPs play an important role in the oral toxicity of BoNTs by protecting toxin from degradation and digestion by gastric acid and proteolytic enzymes. TCs are pH sensitive and can easily dissociate to BoNT and NAPs under neutral to basic pH condition. The stabilization of TCs is critically important for studying interaction domains (NAPs and BoNT), and also to develop better antibodies for the use in BoNT detection methods. In this study, cross-linking of TC was performed with three maleimide base sulfhydryl cross-linking reagents (e.g. 1, 4-bis (maleimido) butane (BMB); 1, 11-bismaleimidotriethyl glycol BM (PEG)3, and Tris (2-maleimidoethyl) amine TMEA) to stabilize TC. Based on cross-linking data of TC, BM (PEG)3 was found to be most suitable amongst three tested cross-linking reagents.