Linked Life Data

6877285

Source:http://linkedlifedata.com/resource/pubmed/id/6877285

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1983-9-23
pubmed:abstractText
A proteolytic enzyme of the liver fluke Fasciola sp. was purified as described previously by ammonium sulfate fractionation, gel filtration on Sephadex G-200 column and L-phenylalanine-agarose chromatography. Leupeptin, a peptide aldehyde of microbial origin, competitively inhibited the enzyme activity with respect to the substrate alpha-N-benzoyl-L-argininamide; the apparent Ki value for leupeptin is 45 000-fold less than the apparent Km for the substrate. Incubation of the enzyme with leupeptin resulted in time-dependent inactivation of the globinolytic activity, with an inactivation constant (Kinact) of 0.4 microM giving the half-maximum inactivation velocity, and with a minimum inactivation half-time (T) of 2.7 min at infinite concentration of this compound. The inactivated enzyme was not reactivated by extensive dialysis. These results imply that leupeptin yields an affinity labelling of an active site of the enzyme. The activity of the Fasciola proteolytic enzyme was also inactivated by other peptide aldehydes and alkylating agents and inactivation constants observed were 0.5 microM for chymostatin, 13 microM for antipain, 2 microM for p-toluenesulfonyl-L-lysine chloromethyl ketone, 140 microM for p-toluenesulfonyl-L-phenylalanine chloromethyl ketone and 40 microM for iodoacetate under the conditions used.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
89-97
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Mechanism of inactivation of a Fasciola proteolytic enzyme by peptide aldehydes and alkylating agents.
pubmed:publicationType
Journal Article