S-S bridges of cathepsin B and H from bovine spleen: a basis for cathepsin B model building and possible functional implications for discrimination between exo- and endopeptidase activities among cathepsins B, H and L.

Bovine spleen cathepsin B contains 7 disulfide bridges. Using different chemical and enzymatic cleavage methods we isolated fragments representing the individual disulfides: Cys14-Cys43, Cys26-Cys71, Cys62-Cys128, Cys63-Cys67, Cys100-Cys132, Cys108-Cys119, and Cys148-Cys252. A similar line of approach was applied to determine the S-S bridges of bovine spleen cathepsin H: Cys23-Cys66, Cys57-Cys99, Cys157-Cys207, and Cys212-Cys5A, where Cys5A is located in the propart portion of the procathepsin H chain.

Disulfide bridges of bovine spleen cathepsin B.

Bovine spleen cathepsin B contains 7 disulfide bridges. Cleavage of the enzyme with cyanogen bromide gives rise to a large and a small fragment. The former contains all disulfide bridges.

Primary structure of cathepsin D inhibitor from potatoes and its structure relationship to soybean trypsin inhibitor family.

A novel effective procedure for the purification of cathepsin D inhibitor from potatoes (PDI) was developed. The amino acid sequence of PDI was determined by analysis of the cyanogen bromide digest and of the limited tryptic and chymotryptic digest of the protein. The inhibitor is a single polypeptide chain protein consisting of 188 residues with a simple sugar moiety attached to Asn-19.

Amino acid sequence of bovine spleen cathepsin B.

The complete amino acid sequence of bovine spleen cathepsin B was determined by manual and automatic Edman degradation of fragments prepared by proteolytic or chemical digestion of the enzyme. The single-chain form of the enzyme consists of 253 amino acid residues and its Mr is 27,468 (carbohydrate moiety not included). The light chain (residues 1-47) and the heavy chain (residues 50-253) of the enzyme are linked by the sequence -Gly-Arg (residues 48 and 49) in the single-chain form.

An acrosin inhibitor from boar seminal vesicle fluid immunologically related to the trypsin-kallikrein inhibitor (Kunitz).

A new acrosin inhibitor was isolated to apparent homogeneity from the fluid of boar seminal vesicles. The inhibitor is immunologically related to the polyvalent trypsin-kallikrein inhibitor from bovine lung known as aprotinin. A crude preparation of the acrosin inhibitor was prepared by immunoaffinity chromatography on anti-aprotinin antibodies bound to Sepharose 4B column.