Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1987-6-5
pubmed:abstractText
The single cysteine on the alpha-subunit of bovine brain S-100a protein has been modified with the thiol specific probe, Acrylodan. When the labelled apoprotein was excited at 380 nm the fluorescence emission maximum was centered at 484 +/- 2 nm, suggesting that the probe is in a fairly hydrophobic environment. Addition of Ca2+ to the protein caused the emission maximum to undergo a red shift to 504 +/- 2 nm, implying that the fluorophore is now more exposed to the solvent. Zn2+, when added to the protein, induced only a small perturbation and the emission maximum shifted to 481 +/- 2 nm. Ca2+ was able to perturb the fluorophore in the presence of Zn2+. 2-p-Toluidinylnaphthalene-6-sulfonate (TNS)-labelled alpha-subunit when excited at 345 nm exhibited very little fluorescence in the absence of Ca2+. Addition of Ca2+ resulted in an increase in TNS fluorescence accompanied by a blue shift of the emission maximum to 445 +/- 1 nm indicating that the probe in the presence of Ca2+ moves to a hydrophobic domain. The fact that Ca2+ and Zn2+ can perturb the labelled sulfhydryl group in the presence of each other clearly demonstrates that the binding sites for the two metal ions must be different on the alpha-subunit as well as on the S-100a protein.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0014-5793
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
214
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35-40
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Fluorescence studies on the Ca2+ and Zn2+ binding properties of the alpha-subunit of bovine brain S-100a protein.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't