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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
1991-2-14
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pubmed:abstractText |
Granzyme B has been purified to homogeneity from the granules of a human cytolytic lymphocyte line, Q31, in an enzymatically active form by a three-step procedure. Q31 granzyme B hydrolyzed Na-t-butyloxycarbonyl-L-alanyl-L-alanyl-L-aspartyl (Boc-Ala-Ala-Asp) thiobenzyl ester with a kcat of 11 +/- 5 mol/s/mol enzyme and catalytic efficiency kcat/Km of 76,000 +/- 44,000 M-1 s-1. The hydrolysis of Boc-Ala-Ala-Asp thiobenzyl ester by crude Q31 Percoll fractions paralleled the tryptase activity for granule-containing fractions, which showed that granzyme B was associated with granules. When chromatographed on Sephacryl S-300, Q31 granzyme B eluted in two broad bands corresponding to dimer and monomer, both of which electrophoresed at 35 kDa in reducing NaDodSo4 polyacrylamide, and both of which showed a lag phase in assays. The lag phase in assays could be extended with 0.03 mM pepstatin. Upon elution from ion-exchange chromatography Q31 granzyme B electrophoresed at 32 kDa in reducing NaDodSO4 polyacrylamide and did not have a lag phase in assays. The amino-terminal sequence of the 32-kDa Q31 granzyme B was identical to four other human cytotoxic T-lymphocyte granzymes B in 18 of 18 positions sequenced. Purified Q31 granzyme B had a preference for substrates with Glu or Asp as the residue amino-terminal to the scissile bond; little or no activity was noted with oligopeptide substrates for trypsin-like, chymotrypsin-like, and elastase-like proteases. Human plasma alpha 1-protease inhibitor, human plasma alpha 2-protease macroglobulin, soybean and lima-bean trypsin inhibitors, bovine aprotinin, phosphoramidon, and chymostatin inhibited Q31 granzyme B. The inhibition by alpha 1-protease inhibitor was rapid enough to be of physiological significance.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
5
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pubmed:volume |
266
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
98-103
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1985927-Amino Acid Sequence,
pubmed-meshheading:1985927-Cell Line,
pubmed-meshheading:1985927-Chromatography, Gel,
pubmed-meshheading:1985927-Chromatography, High Pressure Liquid,
pubmed-meshheading:1985927-Chromatography, Ion Exchange,
pubmed-meshheading:1985927-Cytoplasmic Granules,
pubmed-meshheading:1985927-Granzymes,
pubmed-meshheading:1985927-Humans,
pubmed-meshheading:1985927-Kinetics,
pubmed-meshheading:1985927-Molecular Sequence Data,
pubmed-meshheading:1985927-Protease Inhibitors,
pubmed-meshheading:1985927-Serine Endopeptidases,
pubmed-meshheading:1985927-Substrate Specificity,
pubmed-meshheading:1985927-T-Lymphocytes, Cytotoxic
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pubmed:year |
1991
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pubmed:articleTitle |
Human cytotoxic lymphocyte granzyme B. Its purification from granules and the characterization of substrate and inhibitor specificity.
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pubmed:affiliation |
Merck, Sharp and Dohme Research Laboratories, Rahway, New Jersey 07065.
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pubmed:publicationType |
Journal Article
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