Merck, 204888-5MG, Complement C5, Human

General description
Native, human C5 complement component. Glycoprotein composed of two non-identical subunits of M.W. 120,000 (α) and 75,000 (β) linked by disulfide bonds. Present in normal human serum at 70 µg/ml. Activation of complement via either the classical or alternative pathway can result in assembly of C5-cleaving enzymes (C5 convertases) on target surfaces. Both C5 convertases cleave the C5 α-chain at the peptide bond 74, resulting in production of C5a (M.W. 11,200) and C5b fragments (M.W. 185,000). Released C5a peptide is one of the three complement-derived anaphylatoxins. C5b fragment combines with C6, C7, C8, and C9 to form the lytic C5b-9 complement membrane attack complex (MAC).
Biochem/physiol Actions
≥100,000 C₅H₅0 units/mg; ≥60% of the C5 activity in normal human serum on a mg/mg basis
Packaging
Please refer to vial label for lot-specific concentration.
Physical form
In PBS, pH 7.2.
Preparation Note
Following initial thaw, aliquot and freeze (-70°C).
Prepared from serum that has been shown by certified tests to be negative for HBsAg and for antibodies to HIV and HCV.
Other Notes
Janatova, J. 1988. Methods Enzymol. 162, 579.
Wetsel, R.A., et al. 1980. J. Immunol. Methods 35, 319.
Legal Information
CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany
Disclaimer
Toxicity: Standard Handling (A)