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Cobra Venom Factor Protein, Recombinant - 50 µg (CAT#: CB-P273-AB) Datasheet

Product Type
This is a recombinant form of Cobra Venom Factor (CVF). The complement system is the first line of defense against pathogens and an important part of innate and immune adaptability. CVF is a non-toxic complement activating protein in the venom of the cobra species Naja Kaouthia. CVF is a structural and functional analog of complement C3. The protein is functionally similar to C3b and exhibits a triple-stranded structure similar to C3c. In the presence of factor D and Mg2 +, CVF and factor B form a C3/C5 convertase, thereby activating the alternative pathway of complement. Although functionally similar, there are two differences between CVF, Bb convertase and natural C3b, Bb convertase. First, stability is completely different. C3b and Bb have a short life span with a half-life of 1.5 minutes, while CVF and Bb are quite stable with a half-life of 7 hours. Second, factor H decomposes C3b and Bb, and acts as a cofactor for factor I to proteolytically inactivate C3b. CVF convertase is completely resistant to factors H and I. This makes it an excellent research tool. CVF is a widely used reagent for depleting serum samples to study the role of complement in host defense, immune response and disease pathogenesis. As the cobra species has been included in the endangered species list, local CVF is becoming increasingly difficult to obtain. Recombinant protein (rCVF) is synthesized in insect cells and processed into a two-chain form of the original CSF similar in structure to C3 (Vogel et al.). Pro-CVF can exist in three forms and has all the functional activities of mature natural CVF. The activity of pre-CVF and the resulting invertase are no different from CVF and C3b, Bb invertase. rCVF can be used in vitro and in animals. This leads to serum imbalances and high levels of complement end products (such as C3a, C5a and sTCC).
50 µg
PBS, pH 7.4
Functional studies, Western blot
Application Notes
The use of diluent depends on the detection system used. It is recommended that users test reagents and determine their own optimal dilution.
W: Reduce sample handling and use SDS-Page. The band size is approximately 150 kDa.
FS: Complement activation after incubation with CVF is tested by lysis of sheep red blood cells.
Storage Instructions
Product should be stored at -80°C. Repeated freeze and thaw cycles will cause loss of activity. Use C5 protein within 26 hours after thawing and keep on ice. Remainder amounts should be aliquoted and immediately re-freezed for future use. Aliquots should never be thawed more than once. Under recommended storage conditions, product is stable for at least one year.
Cobra Venom Factor
Alternative Names

All products and services are for Research Use Only. Do Not use in humans.


Creative Biolabs has established a team of customer support scientists ready to discuss ADCC/CDC optimization strategies, antibody production, bioinformatics analysis and other molecular biology/biotechnology issues.

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