Linked Life Data

1328658

Source:http://linkedlifedata.com/resource/pubmed/id/1328658

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1992-10-26
pubmed:abstractText
The enzyme-like kinetic properties of precipitated magnesium phosphate as a catalyst for formation of pyrophosphate (PPi) from phospho(enol)pyruvate (PEP) are described. This synthesis occurs at a low temperature (37 degrees C) and represents a model that may help us understand the relevance to chemical evolution of minerals as ancient catalysts whose functions could have been taken over by contemporary enzymes. An insoluble Pi.Mg matrix was formed in a medium with 80% of the water replaced by dimethyl sulfoxide as a way of simulating conditions in a drying pond. Phospho(enol)pyruvate adsorbs onto the Pi.Mg surface according to a Langmuir isotherm, and the PEP concentration dependence of PPi formation follows a Michaelian-like function. A yield of 33% for transformation of the initially adsorbed PEP into PPi was attained after 4 days of incubation with equimolecular concentrations of Pi, MgCl2, and PEP. The magnesium concentration dependence for Pi and Mg precipitation, for adsorption of PEP onto solid Pi.Mg, and for PPi formation showed complex cooperative behavior. These results taken as a whole lead to the conclusion that the Pi.Mg surface not only provides a reactant for PPi formation but also catalyzes the reaction.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-2844
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
277-85
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Pyrophosphate synthesis from phospho(enol)pyruvate catalyzed by precipitated magnesium phosphate with "enzyme-like" activity.
pubmed:affiliation
Departamento de Bioquímica, Universidade Federal do Rio de Janeiro, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't