Linked Life Data

2125489

Source:http://linkedlifedata.com/resource/pubmed/id/2125489

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
1991-2-22
pubmed:abstractText
The original proposal of Saier stating that P-enolpyruvate-dependent mannitol phosphorylation is catalyzed by the monomeric form of the bacterial phosphotransferase enzyme IImtl, which would be the form predominantly existing in the phospholipid bilayer, whereas mannitol/mannitol-P exchange would depend on the transient formation of functional dimers, is refuted [Saier, M.H. (1980) J. Supramol. Struct. 14, 281-294]. The correct interpretation of the proportional relation between the rate of mannitol phosphorylation in the overall reaction and the enzyme concentration is that enzyme IImtl is dimeric under the conditions employed. Differences measured in the enzyme concentration dependency of the overall and exchange reactions were caused by different assay conditions. The dimer is favored over the monomer at high ionic strength and basic pH. Mg2+ ions bind specifically to enzyme IImtl, inducing dimerization. A complex formed by mixing inorganic phosphate, F-, and Mg2+ at sufficiently high concentrations inhibits enzyme IImtl, in part, by dissociation of the dimer. Enzyme IImtl was dimeric in 25 mM Tris, pH 7.6, and 5 mM Mg2+ over a large enzyme concentration range and under many different turnover conditions. The association/dissociation equilibrium was demonstrated in phosphate bufers, pH 6.3. The dimer was the most active form both in the overall and in the exchange reaction under the conditions assayed. The monomer was virtually inactive in mannitol/mannitol-P exchange but retained 25% of the activity in the overall reaction.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10120-5
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Subunit structure and activity of the mannitol-specific enzyme II of the Escherichia coli phosphoenolpyruvate-dependent phosphotransferase system solubilized in detergent.
pubmed:affiliation
Department of Physical Chemistry, University of Groningen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't