Linked Life Data

7019702

Source:http://linkedlifedata.com/resource/pubmed/id/7019702

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1981-9-22
pubmed:abstractText
The NADP-linked malic enzyme (EC 1.1.1.40) from the insect flagellate Crithidia fasciculata has been purified to electrophoretic homogeneity by a procedure involving ammonium sulphate fractionation, gel filtration on Sephadex G-200, and column chromatography on DEAE-cellulose and hydroxylapatite. The regulatory properties of the purified enzyme have been studied, and compared with those of the two forms malic enzyme (I and II) present in Trypanosoma cruzi. The enzyme from C. fasciculata, like malic enzyme II from T. cruzi was activated by L-aspartate and succinate, which decreased the apparent Km values for both substrates, L-malate and NADP; L-aspartate in addition increased the apparent Vmax. The enzyme from C. fasciculata was inhibited by oxaloacetate, which was strictly competitive towards L-malate, with an apparent Ki (26 microM) intermediate between those reported for the two enzyme forms from T. cruzi. The C. fasciculata enzyme, like malic enzyme II from T. cruzi, was inhibited by adenine nucleotides, which were competitive towards both substrates; in addition, it was inhibited by acetyl-CoA, glyoxylate and NADH, which affected very little the activity of both enzyme froms forms T. cruzi. Thus the malic enzyme from C. fasciculata showed a regulatory pattern even more complex than that of the same enzyme from T. cruzi, despite the fact that there seems to be only one enzyme, present in the cytosol, in the insect trypanosomatid.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
Purification and regulatory properties of the NADP-linked malic enzyme for Crithidia fasciculata.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't