In the past, fluorescence emission from an extrinsic fluorophore bound to heme-proteins would only be studied with the removal of the heme since fluorescence from the flurophore could not be detected using right-angle optics. Using front-face fluorometry, a significant steady state emission signal originating from the probe bound to hemoglobin is detected. This is the first report of the detection of extrinsic fluorescence of a probe bound to a heme-protein. We also demonstrate that the extrinsic probe, 5-iodoacetamidofluorescein, is covalently bound to hemoglobin, specifically at β93 Cysteine. Ligand binding results in a change in the fluorophore fluorescence intensity as predicted by hemoglobin crystallographic studies. Efficiency of energy transfer measurements are made.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jul 16 1986|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology