Background : Numerous spider toxins are of interest as tools for neurophysiological research or as lead molecules for the development of pharmaceuticals and insecticides. Direct detection and identification of the interacting proteins of a spider toxin are helpful for its action-mechanism analysis and practical application. The present study employed a combinative strategy for the analysis of interacting proteins of huwentoxin-IV (HWTX-IV), a peptidic neurotoxin from the venom of the spiderSelenocosmia huwena.Results : HWTX-IV was first lightly labeled with biotin under the optimized mild experimental conditions and the toxin labeled with a single biotin group (monobiotinylated HWTX-IV) was demonstrated by electrophysiological experiments to retain its original bioactivity and was used in combination with far-western blotting to detect its interacting proteins. Comparative experiments indicated that some membrane proteins from rat neuromuscular junction preparations bind to monobiotinylated HWTX-IV after being transferred onto a PVDF membrane from the SDS-gel. With capillary high performance liquid chromatography-tandem mass spectrometry, several membrane proteins with which HWTX-IV potentially interacted were identified from the preparations and then bioinformatically analyzed.Conclusions : This work has provided not only a new insight into the action mechanism of HWTX-IV but also a reference technology for the relevant researches.

Perovskite-type mixed conducting oxides of SrCo1-ySc yO3-δ (y=0.02-0.7) were synthesized by a combined EDTA-citrate complexing method. Different scandium doping concentrations in SrCo1-ySc yO3-δ have significant effects on the phase structure, electrical conductivity, surface properties and oxygen permeation behaviour of the resultant membranes. SrCoO3-δ without scandium incorporation displayed a 2H BaNiO3-type structure with almost zero oxygen flux at high temperatures. Small amounts of Sc2O3 doping (y<0.1) efficiently stabilized the oxide in a cubic perovskite structure, leading to a sharp increase in the permeation flux, with a maximum value of 3.1ml.cm-2.min-1 achieved at 900ºC for SrCo0.95Sc0.05O3-δ and SrCo0.9Sc0.1O3-δ membranes. The permeation process could be rate-limited by either the oxygen bulk diffusion, oxygen surface exchange, or a combination of both depending on the scandium doping level. Further increases of the Sc3+ doping concentration (y>0.1) were found to lower the membrane oxygen fluxes, with y³≥0.4 doped SrCo1-ySc yO3-δ ceramics no longer showing any oxygen permeation.

In this study, two laboratory-scale simulated landfill bioreactors were established, of which Reactor A was operated only with leachate recirculation and served as the control, and Reactor B was operated as semi-aerobic bioreactor landfill with leachate recirculation. In situ leachate treatment and accelerating organic decomposition in semi-aerobic bioreactor landfill was investigated. The results indicated that the introduction of air into the landfill was favourable for optimising the micro-organism growth environment and accelerating the degradation of organic matter. It can be seen clearly from the results that NH4+-N can be removed in situ in the semi-aerobic bioreactor landfill with leachate recirculation. Moreover, semi-aerobic bioreactor landfill showed lower emissions for leachate than those in leachate from anaerobic landfill, with low concentrations of COD, VFA, NH4+-N and TKN, and which saved the disposing process of the discharged leachate. The three-dimensional excitation-emission matrix fluorescence spectroscopy (EEMs) of dissolved organic matter (DOM) in Reactor B changed greatly, and fluorescence peak changed from protein-like fluorescence at Day 60 to humic-like fluorescence at Day 95 and 250, while in Reactor A, fluorescence peak of DOM was always protein-like fluorescence. The comparison of the EEMs indicated that the semi-aerobic landfill accelerated the organic decomposition.