| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
* Department of Biophysics, and Department of General Zoology and Endocrinology, University of Ulm, Ulm, Germany; and Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois
Correspondence: Address reprint requests to Gerd Ulrich Nienhaus, Dept. of Biophysics, University of Ulm, 89069 Ulm, Germany. Tel.: 49-731-502-3050; Fax: 49-731-502-3059; E-mail: uli{at}uiuc.edu.
Red fluorescent proteins are important tools in fluorescence-based life science research. Recently, we have introduced eqFP611, a red fluorescent protein with advantageous properties from the sea anemone Entacmaea quadricolor. Here, we have studied the submillisecond light-driven intramolecular dynamics between bright and dark states of eqFP611 and, for comparison, drFP583 (DsRed) by using fluorescence correlation spectroscopy on protein solutions. A three-state model with one dark and two fluorescent states describes the power-dependence of the flickering dynamics of both proteins at different excitation wavelengths. It involves two light-driven conformational transitions. We have also studied the photodynamics of individual (monomeric) eqFP611 molecules immobilized on surfaces. The flickering rates and dark state fractions of eqFP611 bound to polyethylene glycol-covered glass surfaces were identical to those measured in solution, showing that the bound FPs behaved identically. A second, much slower flickering process was observed on the 10-ms timescale. Deposition of eqFP611 molecules on bare glass surfaces yielded bright fluorescence without any detectable flickering and a >10-fold decreased photobleaching yield. These observations underscore the intimate connection between protein motions and photophysical processes in fluorescent proteins.
This article has been cited by other articles:
 |
|
 |
|
  D. Zhang, H. Lans, W. Vermeulen, A. Lenferink, and C. Otto Quantitative Fluorescence Correlation Spectroscopy Reveals a 1000-Fold Increase in Lifetime of Protein Functionality Biophys. J., October 1, 2008; 95(7): 3439 - 3446. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Hendrix, C. Flors, P. Dedecker, J. Hofkens, and Y. Engelborghs Dark States in Monomeric Red Fluorescent Proteins Studied by Fluorescence Correlation and Single Molecule Spectroscopy Biophys. J., May 15, 2008; 94(10): 4103 - 4113. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. Petrasek and P. Schwille Precise Measurement of Diffusion Coefficients using Scanning Fluorescence Correlation Spectroscopy Biophys. J., February 15, 2008; 94(4): 1437 - 1448. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Ivanchenko, S. Glaschick, C. Rocker, F. Oswald, J. Wiedenmann, and G. U. Nienhaus Two-Photon Excitation and Photoconversion of EosFP in Dual-Color 4Pi Confocal Microscopy Biophys. J., June 15, 2007; 92(12): 4451 - 4457. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. S. Dittrich, S. P. Schafer, and P. Schwille Characterization of the Photoconversion on Reaction of the Fluorescent Protein Kaede on the Single-Molecule Level Biophys. J., November 1, 2005; 89(5): 3446 - 3455. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Nienhaus, G. U. Nienhaus, J. Wiedenmann, and H. Nar Structural basis for photo-induced protein cleavage and green-to-red conversion of fluorescent protein EosFP PNAS, June 28, 2005; 102(26): 9156 - 9159. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. E. Manolov, C. Rocker, V. Hombach, G. U. Nienhaus, and J. Torzewski Ultrasensitive Confocal Fluorescence Microscopy of C-Reactive Protein Interacting With Fc{gamma}RIIa Arterioscler. Thromb. Vasc. Biol., December 1, 2004; 24(12): 2372 - 2377. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
