Abstract
Frequency-domain fluorescence measurements to 2 GHz were able to recover and account for essentially all of the intrinsic tyrosine anisotropy of calmodulin and its proteolytic fragments containing one or two tyrosine residues. Low-temperature measurements have detected a very rapid initial anisotropy decay in the 2-tyrosine species which may be attributed to radiationless energy transfer between the two tyrosines. The observed values of the rotational correlation times indicate that both tyrosines of calmodulin possess considerable mobility, which decreases in the presence of Ca2+ and at low temperatures.
Original language | English |
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Pages (from-to) | 69-78 |
Number of pages | 10 |
Journal | Biophysical Chemistry |
Volume | 39 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1991 |
Keywords
- Anisotropy
- Ca
- Calmodulin
- Energy transfer
- Fluorescence
- Protein dynamics
- Tyrosine