title: A comparison of four sulfhydryl cathepsins (B, C, H, and L) from porcine spleen.
abstract: Four sulfhydryl cathepsins, B, C (dipeptidyl aminopeptidase I), H, and L were isolated from porcine spleen. They are all glycoproteins of similar amino acid compositions, which are comparable with those of cathepsins B and H from other sources and so with papain. All four cathepsins exist in multiple charged forms: B, C, H, and L have isoelectric points in the range 4.3-5.4, 5.3 and 5.9, 5.2-5.7, and 7-8.7, respectively. The molecular weights of cathepsins B and H were 24 000 and 26 000. Anomalous behaviour of cathepsin L on both conventional gel filtration and high pressure liquid chromatography precluded a precise assessment of its weight which is between 22 000 and 28 000. The isolated mercurial derivative of cathepsin C has a molecular weight of 56 000 (an active dimer formed on reduction). Cathepsins B and H also aggregate.
mesh_terms: D000818:Animals; D002384:Catalysis; D002401:Cathepsin B; D020789:Cathepsin C; D056655:Cathepsin H; D056668:Cathepsin L; D002403:Cathepsins / Q000302:isolation & purification*; D003546:Cysteine Endopeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000302:isolation & purification; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases; D007525:Isoelectric Focusing; D008970:Molecular Weight; D013154:Spleen / Q000201:enzymology*; D013552:Swine / Q000378:metabolism*
chemical_list: D002403:Cathepsins; D010450:Endopeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D020789:Cathepsin C; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056668:Cathepsin L; D056655:Cathepsin H