Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1975-10-7
pubmed:abstractText
The mode of inhibition by alpha-1-antitrypsin of chymotrypsin, trypsin and pancreatic elastase was examined by a kinetic method. All three enzymes were completely bound to alpha-1-antitrypsin; therefore, the dissociation constant of the enzyme-inhibitor complex was too low to measure with these methods. The dissociation constants for the three enzyme-inhibitor complexes were estimated to be less than 5 - 10 minus 9 M. However, alpha-1-antitrypsin could be specifically displaced from Sepharose-bound elastase with an irreversible inhibitor of that enzyme. Additional experiments showed that dioxane, 20% (v/v), blocked 100% of the inhibition of elastase, 16% of the inhibition of trypsin, and 0% of the inhibition of chymotrypsin. The effect was reversed by diluting the dioxane to 1% (v/v). These findings indicated that alpha-1-antitrypsin was tightly bound to the three enzymes studied but did not allow discrimination as to the nature of the inhibition. However, the competitive mode of inhibition was suggested by the displacement of alpha-1-antitrypsin from elastase by an irreversible inhibitor of the enzyme that bound covalently at the enzyme-active site. The variable susceptibility of the enzyme to blockage of the inhibition by low concentrations of p-dioxane suggested that hydrophobic bonds may be important in the interaction with alpha-1-antitrypsin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
391
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
193-200
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
The interaction of alpha-1-antitrypsin with chymotrypsin, trypsin and elastase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.