Linked Life Data

10224162

Source:http://linkedlifedata.com/resource/pubmed/id/10224162

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1999-7-22
pubmed:abstractText
Phospholipase A2 activity against mixed monolayers of dilauroylphosphatidic acid or dilauroylphosphatidylcholine with glycosphingolipids can be reversibly modulated by external constant electrostatic fields. The changes of enzymatic activity are correlated to the depolarization or hyperpolarization of the film caused by specific dipolar properties of glycosphingolipids. Hyperpolarizing fields enhance the enzymatic activity against pure dilauroylphosphatidic acid while depolarizing fields induce a decrease of activity. Compared to the pure substrate, the interface of mixed films containing neutral glycosphingolipids or gangliosides is already partially depolarized and the magnitude of activation induced by an external hyperpolarizing field is decreased; conversely, depolarizing fields cause an increased inhibition of activity. Differing from gangliosides, sulfatides bring about a hyperpolarization of the mixed lipid monolayer and external hyperpolarizing or depolarizing fields cause enhanced activation and reduced inhibition, respectively. The effects of glycosphingolipids depend on their relative proportion in the monolayer. Results were similar with dilauroylphosphosphatidylcholine but the field effects were less than half of those found with dilauroylphosphatidic acid. Our work shows that the activity of phospholipase A2 in addition to responding reversibly to external electrostatic fields, is directly modulated by the polarity and magnitude of the lipid polar head group dipole moments.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-2275
pubmed:author
pubmed:issnType
Print
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
930-9
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Modulation of phospholipase A2 by electrostatic fields and dipole potential of glycosphingolipids in monolayers.
pubmed:affiliation
Departamento de Quimica Biológica-CIQUIBIC, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Agencia Postal 4, CC 61, 5000 Córdoba, Argentina.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't