85-1380-52　［取扱停止］Carboxypeptidase B, PMSF Treated 3KU　CAS No:9025-24-5　C1205-05

特徴

• Carboxypeptidase B (CPB) catalyzes hydrolysis of the basic amino acids, lysine, arginine, and ornithine from the C-teminal position in polypeptides. It occurs as a zymogen in the pancreas of most vertebrates. Because of its high specificity for C-terminal basic amino acids it has found wide use in end-group analysis for sequence determination.
• Appearance:Supplied as a solution in 0.1M sodium chloride
• Treated with PMSF to inhibit protease activity.
• Activity:≥70 units/mg protein≥3000 units/ml
• Unit Definition:1 unit hydrolyzes 1 micromole of hippuryl-L-arginine per minute at 25°C, pH 7.65.
• Chymotrypsin:≤0.02%
• Trypsin:≤0.02%
• COA:≤2%
• Molecular Weight:34,300 (Folk et al. 1960).
• Composition:The enzyme contains 1 gram atom of zinc per mole; the amino acid composition has been determined (Folk 1971). Studies on binding sites have been reported by Moore and Benoiton (1975), Roholt and Pressman (1975), Zisapel et al. (1973b), Zisapel and Sokolovsky (1972). See also Werber et al. (1975) and Zisapel et al. (1975).
• Optimum pH:9.0 (Wolff et al. 1962)
• Extinction Coefficient:21.4 (Folk 1971)
• Specificity:Porcine CPB shows minimal if any activity toward CPA substrates (Folk 1971). See Zisapel et al. (1973a) and Sokolovsky and Zisapel (1971), also Seely and Benoiton (1969) and Jones and Miller (1968).
• Inhibitors:CPB is competitively inhibited by arginine, lysine, and ornithine. See Wolff et al. (1962) for kinetic parameters. The enzyme is not inhibited by diisopropylfluorophosphate (DFP) or phenylmethylsulfonyl flouride (PMSF) but is inhibited by metal chelating agents like 1,10-phenanthroline.
• Quality Control:SDS-PAGE
• Storage and Stability:May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 6 months after receipt at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.