Description_x000D_ General description_x000D_ Extinction Coefficient: E1% = 21.0 (280 nm)_x000D_ pI: 9.0_x000D_ Packaging_x000D_ 1000 units in poly bottle_x000D_ Biochem/physiol Actions_x000D_ Ficin is classified as a thiol protease. It contains a single reactive cysteine at its active site. The amino acid homology of the active site is similar to that of papain. Ficin will cleave proteins at the carboxyl side of Gly, Ser, Thr, Met, Lys, Arg, Tyr, Ala, Asn, and Val. The reported Km for the chromogenic substrate pGlu-Phe-Leu-p-nitroanilide is 0.43 mM. Ficin is inhibited by iodoacetamide, iodoacetic acid, N-ethylmaleimide, mercuric chloride, DFP (diisopropyl fluorophosphate), TLCK (Na-p-Tosyl-lysine chloromethyl ketone), and TPCK (N-Tosyl-L-phenylalanine chloromethyl ketone). Ficin can be used to generate high yielding F (ab')2 fragments from mouse IgG1._x000D_ Unit Definition_x000D_ One unit will produce a ΔA280 of 1.0 per min at pH 7.0 at 37 °C when measuring TCA soluble products from casein in a final volume of 10 ml (1 cm light path)._x000D_ The enzyme is soluble in 1 M potassium phosphate buffer, pH 7.0 (0.25 mg/ml), yielding a clear solution.