During the long-term evolution，animals such as amphibians, reptiles and insects produce rich proteins and peptides in their venom gland secretions. These proteins show high activity and strong specificity towards their substrate, which provide perfect models for the research of protein structure and function. They can also be used as powerful tools to study the human pathogenesis of diseases and physiological mechanism. And they are also natural pools for the development of clinical diagnosis reagent and therapy drug. Cobra venom factor (CVF) is an anti-complement factor existed in cobra venom. It is a functional analogue of C3b. Like C3b, it binds factor B in the presence of Mg2+ ions. This new formed complex can be cleaved by factor D, then generates a complex CVF,Bb and a peptide Ba. CVF,Bb is a C3/C5 convertase which is resistant to the regulation of factor H and I. Different CVFs have different levels of C5 hydrolytic activity. CVF has been used as experimental tool to decomplement laboratory animals to study the functions of complement in host defense and immune response as well as in the pathogenesis of diseases. In the present work, a cobra venom factor termed OVF was purified and characterized from the venom gland secretions of Ophiophagus hannah by successive gel fltration, ion-exchange and heparin affinity chromatography. The purified OVF was homogenous on SDS-PAGE gel with an apparent molecular weight of 140 KDa under non-reducing conditions. Under reducing condition, OVF divided into three bands with apparent molecular weight of 72 KDa, 45 KDa and 32 KDa， respectively. OVF Consumed complement component with CH50 of 6.5 ug, and activated the bystander lysis of guinea pig erythrocytes. By RT-PCR and 5'RACE method, the full-length cDNA were also obtained. Result of MALDI-TOF assay indicated the cloned cDNA matched the OVF protein very well. Alignment of OVF’s deduced protein sequence with other known CVFs raveled that it is highly conserved. The alignment of CVF of all known species and cobra C3 reveal CVFs are high conservative molecules with identity above 80% between each other. The Phylogentic studies reveled OVF is closer to CVF from Naja kaouthia CVF than AVF-1, and AVF-2. In wasp venom, Phospholipase is a main allergen to human. However, the Phospholipases from wasp venoms also have other bioactivities including inducing hemolysis, inducing inflammation, activating platelet aggregation, inducing thrombosis in vivo and lethal activity. A protein named Vtp32 with molecular weight of 32 kDa was purified from the venom gland secretions of Vespa tropica by successive gel filtration and heparin affinity chromatography. Vtp32 showed PLA1 activity. Egg yolk lecithin treated by Vtp32 can lysis the erythrocytes. Beside Vtp32 has anti-coagulation activity, this is the first report about the anti-coagulation phospholipase in wasp venom. Whey acidic protein (WAP) is the protein with (four disulphide core, FDC) domain. The FDC domain of WAP can also called WFDC domain. In the cDNA library of Bombina maxima, we found ten clones that coding WFDC domain, six of which contain the entire open reading frame. So it implies that WAP is abundant in the skin secretion of Bombina maxima. In order to isolate Bombina maxima WAP and reveal it’s bioactivities, we expressed the WFDC domain of WAP with pMal p2×expression system. The fusion protein fuse with maltose-binding protein (MBP) is purified by amylase resin Column. The New Zealand big ear rabbit is inoculated by the purified protein and the polyclone antibody was collected and purified. The purified antibody can detect the expressed fusion prtotein. Proteins with molecular weight of 17 kDa in the Bombina maxima skin secretion were also detected by the purified antibody. So it is confirmed that WAP indeed exist in Bombina maxima skin secretion.
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