Linked Life Data

6437444

Source:http://linkedlifedata.com/resource/pubmed/id/6437444

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1985-1-14
pubmed:abstractText
Purified mannitol-specific enzyme II (EIImtl), in the presence of the detergent Lubrol, catalyzes the phosphorylation of mannitol from P-HPr via a classical ping-pong mechanism involving the participation of a phosphorylated EIImtl intermediate. This intermediate has been demonstrated by using radioactive phosphoenolpyruvate. Upon addition of mannitol, at least 80% of the enzyme-bound phosphoryl groups can be converted to mannitol 1-phosphate. The EIImtl concentration dependence of the exchange reaction indicates that self-association is a prerequisite for catalytic activity. The self-association can be achieved by increasing the EIImtl concentration or at low concentrations of EIImtl by adding HPr or bovine serum albumin. The equilibrium is shifted toward the dissociated form by mannitol 1-phosphate, resulting in a mannitol 1-phosphate induced inhibition. Mannitol does not affect the association state of the enzyme. Both mannitol and mannitol 1-phosphate also act as classical substrate inhibitors. The apparent Ki of each compound, however, is approximately equal to its apparent Km, suggesting that mannitol and mannitol 1-phosphate bind at the same site on EIImtl. Due to strong inhibition provided by mannitol and mannitol 1-phosphate in the exchange reaction, the kinetics of this reaction cannot be used to determine whether the reaction proceeds via a ping-pong or an ordered reaction mechanism.
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
9
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4934-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Kinetics and subunit interaction of the mannitol-specific enzyme II of the Escherichia coli phosphoenolpyruvate-dependent phosphotransferase system.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't