Linked Life Data

2525924

Source:http://linkedlifedata.com/resource/pubmed/id/2525924

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1989-8-17
pubmed:abstractText
We examined the tryptophan decay kinetics of sarcoplasmic reticulum Ca2+-ATPase using frequency-domain fluorescence. Consistent with earlier reports on steady-state fluorescence intensity, our intensity decays reveal a reproducible and statistically significant 2% increase in the mean decay time due to calcium binding to specific sites involved in enzyme activation. This Ca2+ effect could not be eliminated with acrylamide quenching, which suggests a global effect of calcium on the Ca2+-ATPase, as opposed to a specific effect on a single water-accessible tryptophan residue. The tryptophan anisotropy decays indicate substantial rapid loss of anisotropy, which can be the result of either intramolecular energy transfer or a change in segmental flexibility of the ATPase protein. Energy transfer from tryptophan to TNP-ATP in the nucleotide binding domain, or to IEADANS on Cys-670 and -674, indicates that most tryptophan residues are 30 A or further away from these sites and that this distance is not decreased by Ca2+. In light of known structural features of the Ca2+-ATPase, the tryptophan fluorescence changes are attributed to stabilization of clustered transmembrane helices resulting from calcium binding.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3490-8
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Characterization of the tryptophan fluorescence from sarcoplasmic reticulum adenosinetriphosphatase by frequency-domain fluorescence spectroscopy.
pubmed:affiliation
Department of Biological Chemistry, School of Medicine, University of Maryland, Baltimore 21201.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't