Linked Life Data

9249011

Source:http://linkedlifedata.com/resource/pubmed/id/9249011

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-8-21
pubmed:abstractText
Chemical modification of Escherichia coli phosphoenolpyruvate carboxylase (P-pyruvate carboxylase) by 2,4,6-trinitrobenzene sulfonate, a specific reagent for amino groups, causes desensitization to allosteric inhibitors, L-aspartate and L-malate, as well as inactivation. When L-malate is included in the modification mixture, P-pyruvate carboxylase was markedly protected from both desensitization and inactivation [Naide, A., Izui, K., Yoshinaga, T. & Katsuki, H. (1979) J. Biochem. (Tokyo) 85, 423-432]. To determine the lysine residue(s) involved in allosteric inhibition, the lysine residues that were protected from modification by L-malate were investigated by analyzing trinitrophenylated peptides liberated by digestion with glutamyl endopeptidase (V8-protease). The identified residues were Lys491, Lys620, Lys650, and Lys773. Each of these residues was individually replaced with an alanine or serine residue by site-directed mutagenesis to produce mutant enzymes. The mutant enzyme whose lysine residue was replaced with serine ([Ser620]P-pyruvate carboxylase) showed a marked desensitization to L-aspartate and L-malate, while retaining almost the same maximal catalytic activity as the wild-type P-pyruvate carboxylase. Essentially no changes in enzymatic properties were observed for the [Ala491]- and [Ala650]P-pyruvate carboxylases, while for the [Ala620]- and [Ala773]P-pyruvate carboxylases the polypeptides of the expected size were not significantly accumulated in the transformed E. coli cells, presumably due to intracellular degradation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
247
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
74-81
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
The replacement of Lys620 by serine desensitizes Escherichia coli phosphoenolpyruvate carboxylase to the effects of the feedback inhibitors L-aspartate and L-malate.
pubmed:affiliation
Department of Chemistry, Faculty of Science, Kyoto University, Sakyo-ku, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't