Linked Life Data

35826

Source:http://linkedlifedata.com/resource/pubmed/id/35826

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1979-7-25
pubmed:abstractText
The positional specificity of the phospholipase A (EC 3.1.1.4) in human gallbladder epithelium has been studied using 14C-phosphatidylethanolamine radiolabeled either in the 1-acyl or in the 2-acyl position. After heating of homogenized epithelial cells at 70 degrees C for 2 min, their lysophospholipase activity was lost. In contrast, the ability to hydrolyze 14C-phosphatidylethanolamine in biosynthetically radiolabeled Escherichia coli was largely retained. The amounts of radioactivity found in the products of hydrolysis under different conditions suggest that there are two different phospholipase A activities in the gallbladder epithelium: one, with optimal activity at pH 7, that requires Ca2+ and is specific for the 2-acyl position, and another, with optimal activity at pH 4, that does not require Ca2+ and that, apart from the 2-acyl position, attacks the 1-acyl position as well. It is possible, therefore, that a complete deacylation of diacylphosphoglycerides in the gallbladder wall is brought about in two different ways: at neutral pH through a combined action of phospholipase A2 and lysophospholipase, the latter being able to hydrolyze the 1-acyl-lysophosphoglyceride, and, at acid pH, through the action of phospholipase A1 and A2 activity, presuming 1-acyl- and 2-acyl-lysophosphoglycerides are also attacked. Both these processes have to be considered in order to explain a turnover of diacylphosphoglycerides that physiologically would prevent the accumulation of lytic lysophosphoglycerides. The possible relevance of these findings to the pathogenesis of aseptic cholecystitis is inferred.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0036-5521
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
379-84
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1979
pubmed:articleTitle
The prerequisites for local lysolecithin formation in the human gallbladder. III. Demonstration of two different phospholipase A activities.
pubmed:publicationType
Journal Article