Linked Life Data

9535271

Source:http://linkedlifedata.com/resource/pubmed/id/9535271

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-5-18
pubmed:abstractText
Human placental alkaline phosphatase is a membrane-anchored protein. Entrapping the enzyme into a reverse micellar vesicle mimics the in vivo conditions and allows examination of the properties of the enzyme. Placental alkaline phosphatase is enzymatically active in Aerosol-OT/isooctane reverse micelles. Substantially different kinetic behavior of the enzyme has been observed in aqueous or reverse micellar systems. In aqueous solution, Mg2+ is a nonessential activator of the enzyme. In the experiments described in the present report Mg2+ was found to be an inhibitor for the enzyme in reverse micelles. This inhibition is presumably due to a time-dependent conformational change of the enzyme molecule, which resulted in a curvature in the recorder tracings of the enzyme assays. The Mg2+-induced conformational change of the enzyme was completely prevented by phosphate and partially reserved by EDTA. High concentrations of Zn2+ also strongly inhibited enzyme activity in both aqueous and reverse micellar solvent systems, presumably by occupying the Mg2+ (M3) site of the enzyme. However, binding of Zn2+ at the M3 site did not cause conformational change of the enzyme and the enzyme assay tracing was linear. The M3 site of the enzyme is proposed to have a modulatory role in vivo using magnesium ion as the modulator.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0277-8033
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
99-106
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Inhibitory effect of magnesium ion on the human placental alkaline phosphatase-catalyzed reaction in a reverse micellar system.
pubmed:affiliation
Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan, Republic of China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't