Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2048571 | FEBS Letters | 2009 | 6 Pages |
Abstract
The intrinsic fluorescence of two apo-photoproteins has been characterized and its concentration-dependent quenching by coelenterazine has been for the first time applied to determine the apparent dissociation constants for coelenterazine binding with apo-aequorin (1.2 ± 0.12 μM) and apo-obelin (0.2 ± 0.04 μM). Stopped-flow measurements of fluorescence quenching showed that coelenterazine binding is a millisecond-scale process, in contrast to the formation of an active photoprotein complex taking several hours. This finding evidently shows that the rate-limiting step of active photoprotein formation is the conversion of coelenterazine into its 2-hydroperoxy derivative.
Related Topics
Life Sciences
Agricultural and Biological Sciences
Plant Science
Authors
Elena V. Eremeeva, Svetlana V. Markova, Adrie H. Westphal, Antonie J.W.G. Visser, Willem J.H. van Berkel, Eugene S. Vysotski,