Linked Life Data

3543004

Source:http://linkedlifedata.com/resource/pubmed/id/3543004

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-3-4
pubmed:abstractText
A human pituitary-derived serine protease, immunologically identical to human lung tryptase (Smith, T. J., Hougland, M.W., and Johnson, D.A. (1984) J. Biol. Chem. 259, 11046-11051), was found immunohistochemically to be associated with mast cells present in pituitary connective tissue. Western blotting combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated the presence of multiple forms: a major Mr 36,300 form and three minor forms with Mr 32,400, 33,400, and 34,600. Two major forms with Mr 35,600 and 34,100 were detected by affinity labeling with 125I-D-Tyr-Glu-Phe-Lys-Arg-CH2Cl. Treatment of the pituitary tryptase preparation with N-glycosidase F indicated that some of the molecular weight heterogeneity results from N-linked glycosylation. The multiple molecular weight forms appear to have the same NH2-terminal sequence: Ile-Val-Gly-Gly-Gln-Glu-Ala-Pro. Pituitary tryptase has an apparent Mr = 110,000 by gel filtration on Sephadex G-200 in the presence of 0.3 M NaCl, indicating that the enzyme may be a tetramer of Mr = 32,400-36,300 subunits. However, this quaternary structure was not stable to gradient polyacrylamide gel electrophoresis. Human pituitary tryptase was so reactive toward synthetic tripeptide coumarin-containing substrates containing a pair of basic amino acids at the site of cleavage such as benzyloxylcarbonyl-L-Ala-L-Lys-L-Arg-4-methylcoumarin-7-amide (k cat/Km = 2.38 X 10(8) M-1 s-1) that Briggs-Haldane kinetics may apply. The reversible inhibitor NaCl at a concentration of 1 M decreased the k cat/Km for benzyloxylcarbonyl-L-Ala-L-Lys-L-Arg-4-methylcoumarin-7-amide to 6.53 X 10(6) M-1 s-1, which reflected a 100-fold increase in apparent Km. Based on active site titration with fluorescein mono-p-guanidinobenzoate hydrochloride, NaCl had no effect on the number of accessible active sites. Substrate specificity studies with prohormones indicated that pituitary tryptase has a preference for cleaving COOH-terminal to arginine or lysine residues which are preceded by a proline residue 4 or 6 residues NH2-terminal to the site of cleavage.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
262
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1363-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:3543004-Amino Acid Sequence, pubmed-meshheading:3543004-Binding Sites, pubmed-meshheading:3543004-Coumarins, pubmed-meshheading:3543004-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:3543004-Fluoresceins, pubmed-meshheading:3543004-Fluorescent Dyes, pubmed-meshheading:3543004-Histocytochemistry, pubmed-meshheading:3543004-Humans, pubmed-meshheading:3543004-Hydrogen-Ion Concentration, pubmed-meshheading:3543004-Immunologic Tests, pubmed-meshheading:3543004-Kinetics, pubmed-meshheading:3543004-Lung, pubmed-meshheading:3543004-Macromolecular Substances, pubmed-meshheading:3543004-Mast Cells, pubmed-meshheading:3543004-Molecular Weight, pubmed-meshheading:3543004-Peptide Fragments, pubmed-meshheading:3543004-Peptide Hydrolases, pubmed-meshheading:3543004-Pituitary Gland, pubmed-meshheading:3543004-Protein Precursors, pubmed-meshheading:3543004-Sodium Chloride, pubmed-meshheading:3543004-Substrate Specificity
pubmed:year
1987
pubmed:articleTitle
Human pituitary tryptase: molecular forms, NH2-terminal sequence, immunocytochemical localization, and specificity with prohormone and fluorogenic substrates.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't