CATHEPSIN H from human liver Product Number C 8821 Product Description higher in patients with metastatic melanoma than in Cathepsins H (EC.3.4.22.1), like cathepsin L and B, is a those without metastasis. lysosomal cysteine proteinase that plays an important role in protein degradation processes. It belongs to the Reagent group of closely related proteins of the peptidase family Cathepsin H is provided as a frozen liquid containing 1 C1 (papain family of thiol proteases). Cathepsin H is a 25 mg of protein with a specific activity of 1 unit/mg more basic protein than Cathepsin B or L. It functions protein in 50 mM sodium acetate, pH 5.5, with as both an aminopeptidase and endopeptidase. 1 mM EDTA. Cathepsins H, L, S, and B vary in the amino acid side chains that can be accommodated in the specificity Precautions and Disclaimer 2 pockets of their active sites. A distinguishing Please consult the Material Safety Data Sheet for characteristic of Cathepsin H is that it cannot accom- handling recommendations before working with this modate aromatic side chains in P2. Cathepsin H also material. displays considerable amino-peptidase activity. Cathepsin H can be distinguished from Cathepsin S by Storage/Stability its activity on Arg-NHMec and its lack of activity against Store at –20 °C. Avoid repeated freeze-thaw cycles. 2 Z-Phe-Arg-NHMec and against elastin. Do not store in a frost-free freezer. Cathepsin H has a molecular weight of approx 28 kDa. Product Profile It is composed of a minichain (8 amino acids) and a Unit Definition: One unit of Cathepsin H is defined as large chain; the large chain may be split into a heavy the amount of enzyme that liberates one nmole of 7- (177 aa) and a light chain (43 aa). All chains are held amino-4-methylcoumarin from L-Arg 7-amido-4- together by disulfide bonds. Two major forms of the methylcoumarin per minute at pH 6.8 at 40 °C. enzyme with pI values of 6.1 and 6.3 were found by 1 isoelectric focusing. Cathepsin H is stable at an acid Cathepsin H is prepared from tissue shown to be non- pH but is unstable at pH values above 7.0. In heat reactive for HbsAG, antiHBc, and negative for anti-HIV stability studies, Cathepsin H has lost 10-15% and 1 and 2 by FDA approved tests. > 80% activity at 30 min. exposure to 50 °C and 60 °C 3 respectively. pH optima vs. Arg-NNap and azocasein References 3 are 6.8 and 5.5 respectively. 1. Popovic, T., et al., J. Chrom., 615, 243-249 (1993). 2. Xue-Qin, X., et al., Arch. Biochem. Biophys., 299, Cathepsins B, H, and L, have been shown to participate 334-339 (1992). in processes of tumor growth and vascularization. 3. Schwartz, W.N. and Barrett, A.J., Biochem. J., 191, Measurement and localization of cathepsin levels 487-497 (1980). provide valuable information for assessing risk of 4. Kos, J. et al., Int. J. Biol. Markers, 15, 84-89 (2000). 4 relapse and death in cancer patients. Cathepsin H levels in serum have been found to be increased in patients with a wide variety of cancers and significantly RNM 01/02 Sigma brand products are sold through Sigma-Aldrich, Inc. Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side of the invoice or packing slip. .