title: A novel chymotrypsin-like serine proteinase from human lung.
abstract: A novel chymotrypsin-like serine proteinase with an M(r) of 30,000 has been isolated from human lung tissue. The enzyme was active on both the synthetic substrate Suc-Ala-Ala-Pro-Phe-SBzl and azocasein, with a pH optimum of 8.0 and a preference for high concentrations of NaCl for maximum activity. The proteinase was inhibited by diisopropylfluorophosphate, tosyl-phenylalanyl-chloromethane, chymostatin, soybean trypsin inhibitor, alpha-1-antichymotrypsin, and alpha-2-macroglobulin. It was not inhibited by C-1 inhibitor or aprotinin. An N-terminal sequence of IIGGTESKPDSRPYMALLQIVEPAVH indicated that this enzyme is a member of a superfamily of serine proteinases comprising cathepsin G, chymase, and the granzymes; however, it is clearly distinct from these enzymes on the basis of both physical and chemical properties.
authors.affiliation: Department of Hematology and Oncology, Philippsuniversität Marburg.
authors.forename: H H
authors.initials: HH
authors.lastname: Heidtmann
authors.forename: J
authors.initials: J
authors.lastname: Travis
mesh_terms: D000595:Amino Acid Sequence; D002918:Chymotrypsin / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008168:Lung / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012697:Serine Endopeptidases / Q000737:chemistry / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology
chemical_list: D015842:Serine Proteinase Inhibitors; D012697:Serine Endopeptidases; D002918:Chymotrypsin