Linked Life Data

3023121

Source:http://linkedlifedata.com/resource/pubmed/id/3023121

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-1-14
pubmed:abstractText
The Na,K-ATPase partially purified from porcine lens fiber cells (Sen and Pfeiffer, 1982) is stimulated fourfold (specific activity) by treatment with sodium thiocyanate. The optimum conditions are 1.5 M NaSCN, 2 mg protein ml-1 reaction mixture, pH 7.0, with incubation continued for 30 min at 23 degrees C. Sodium docecyl sulphate-gel electrophoresis and [3H]ouabain binding studies indicate that the extent of purity is not increased significantly by the procedure. The high-activity preparation has elevated phospholipid:protein and phosphatidylethanolamine:sphingomyelin ratios compared with the deoxycholate-extracted starting material. The cholesterol:phospholipid ratio and phospholipid acyl group composition are not significantly altered by SCN- treatment. Measurements of 1,6-diphenyl-1,3,5-hexatriene fluorescence polarization show that SNC- treatment produces approximately a 5 degrees C decrease in a membrane phase transition temperature. The phase transition also affects the activation energy of the Na,K-ATPase reaction and probably reflects the onset of the gel to liquid crystalline transition rather than the midpoint location of the transition per se. p-Nitrophenylphosphatase activity and Na,K-ATPase activity in the gel state membrane are also increased by SCN- treatment. Increased specific activity may result, in part, from a membrane fluidity-dependent enzyme activation but is also due, in part, to the expression of latent enzyme activity. Using ouabain-binding data and the specific activity of the activated preparation, it can be shown that the turnover number of the fiber cell enzyme is approximately 1% of that observed in most other tissues.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-4835
pubmed:author
pubmed:issnType
Print
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
315-27
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Persistent stimulation of lens fiber cell Na,K-ATPase by sodium thiocyanate.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't