Linked Life Data

3944096

Source:http://linkedlifedata.com/resource/pubmed/id/3944096

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-3-3
pubmed:abstractText
A protein, previously designated thioltransferase (Askelof, P., Axelsson, K., Eriksson, S., and Mannervik, B. (1974) FEBS Lett. 38, 263-267) was purified to homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and flatbed gel isoelectric focusing. The preparative procedure, a modification of that of Axelsson et al. (Axelsson, K., Eriksson, S., and Mannervik, B. (1978) Biochemistry 17, 2978-2984) and Hatakeyama et al. (Hatakeyama, M., Tanimoto, Y., and Mizoguchi, T. (1984) J. Biochem. (Tokyo) 95, 1811-1818) was faster and higher-yielding than the previous procedures. The purified enzyme has a molecular weight of 11,700 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a pI of 8.8. The amino acid composition of thioltransferase is reported, and it closely resembles that of calf thymus glutaredoxin. The optimal pH for this enzyme was 8.5 when S-sulfocysteine was used as a substrate. The plots of the activity of thioltransferase as a function of S-sulfocysteine and 2-hydroxyethyl disulfide concentrations showed sigmoidal relationships. The K0.5 for S-sulfocysteine was 0.6 mM. The enzyme was very sensitive to sulfhydryl alkylating reagents. Preincubation of the enzyme with disulfide compounds prevented the enzyme from inactivation by iodoacetamide but inhibited the thioltransferase activity in the absence of iodoacetamide. The results suggest that the active center of thioltransferase is cysteine dependent and that substrates may form mixed disulfides with the enzyme. Based on the iodoacetamide inactivation and disulfide protection of thioltransferase activity, a model for the catalytic mechanism of the thiol-disulfide oxidoreduction is proposed.
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
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
996-1001
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Purification and properties of thioltransferase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.