Linked Life Data

7814371

Source:http://linkedlifedata.com/resource/pubmed/id/7814371

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1995-2-3
pubmed:abstractText
A cytosolic high M(r) cysteine-S-conjugate beta-lyase (apparent M(r) of approximately 330,000) has been partially purified from rat kidneys. The high M(r) lyase is also present in the mitochondria. The purified enzyme contains at least two proteins with apparent M(r) values of approximately 50,000 and approximately 70,000. Activity is stimulated by dithiothreitol, alpha-keto acids, and pyridoxal 5'-phosphate; aminooxyacetate is an inhibitor. The enzyme catalyzes a competing (half) transamination reaction between pyridoxal 5'-phosphate cofactor and cysteine-S-conjugate substrate; added alpha-keto acids promote conversion of active site pyridoxamine 5'-phosphate to pyridoxal 5'-phosphate. The enzyme also catalyzes a full (but weak) transamination between L-phenylalanine and alpha-keto-gamma-methiolbutyrate. The purified enzyme is not recognized by polyclonal rabbit antibodies to cytosolic rat kidney glutamine transaminase K (another cysteine-S-conjugate beta-lyase of rat kidney) and has no obvious similarities to other pyridoxal 5'-phosphate-containing enzymes. In addition to catalyzing elimination reactions with S-(1,2-dichlorovinyl)-L-cysteine and S-(1,1,2,2-tetrafluoroethyl)-L-cysteine, the enzyme reacts with leukotriene E4 and 5'-S-cysteinyldopamine. Finally, the cytosolic and mitochondrial enzymes are activated by alpha-ketoglutarate. Thus, the possibility must be considered that, in kidneys of animals exposed to various cysteine conjugates, the high M(r) lyase contributes to the generation of pyruvate, ammonia, and reactive fragments in vivo. Many cysteine conjugates are nephrotoxic, and the high M(r) lyase(s) may be involved.
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
6
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
180-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Isolation from rat kidney of a cytosolic high molecular weight cysteine-S-conjugate beta-lyase with activity toward leukotriene E4.
pubmed:affiliation
Department of Biochemistry, Cornell University Medical College, New York, New York 10021.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.