Linked Life Data

9822815

Source:http://linkedlifedata.com/resource/pubmed/id/9822815

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1999-1-4
pubmed:abstractText
The main mechanism causing catabolite repression in Escherichia coli is the dephosphorylation of enzyme IIAGlc, one of the enzymes of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS). The PTS is involved in the uptake of a large number of carbohydrates that are phosphorylated during transport, phosphoenolpyruvate (PEP) being the phosphoryl donor. Dephosphorylation of enzyme IIAGlc causes inhibition of uptake of a number of non-PTS carbon sources, a process called inducer exclusion. In this paper, we show that dephosphorylation of enzyme IIAGlc is not only caused by the transport of PTS carbohydrates, as has always been thought, and that an additional mechanism causing dephosphorylation exists. Direct monitoring of the phosphorylation state of enzyme IIAGlc also showed that many carbohydrates that are not transported by the PTS caused dephosphorylation during growth. In the case of glucose 6-phosphate, it was shown that transport and the first metabolic step are not involved in the dephosphorylation of enzyme IIAGlc, but that later steps in the glycolysis are essential. Evidence is provided that the [PEP]-[pyruvate] ratio, the driving force for the phosphorylation of the PTS proteins, determines the phosphorylation state of enzyme IIAGlc. The implications of these new findings for our view on catabolite repression and inducer exclusion are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
487-98
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Inducer exclusion in Escherichia coli by non-PTS substrates: the role of the PEP to pyruvate ratio in determining the phosphorylation state of enzyme IIAGlc.
pubmed:affiliation
E.C. Slater Institute, BioCentrum, University of Amsterdam, Plantage Muidergracht 12, 1018 TV Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't