title: Excitation wavelength dependence of the proton-transfer reaction of the green fluorescent protein.
abstract: Picosecond time-correlated single-photon counting was used to measure the proton-transfer rate of green fluorescent protein (GFP) excited by several wavelengths between 266 and 405 nm. When samples of GFP in water and D2O are excited at short wavelengths, lambda(ex) < 295 nm, the fluorescence properties are largely modified with respect to excitation at a wavelength around 400 nm, the peak of the absorption band of the S0 --> S1 transition of the ROH form of the chromophore. The shorter the excitation wavelength, the longer the decay time of the ROH emission band at 450 nm and the longer the rise time of the RO- emission band at 512 nm. The proton transfer is slower by an order of magnitude and about a factor of 3 when GFP in water and D2O are excited by 266 nm, respectively.
authors.affiliation: Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel. huppert@tulip.tau.ac.il
authors.forename: Dan
authors.initials: D
authors.lastname: Huppert
authors.forename: Pavel
authors.initials: P
authors.lastname: Leiderman
authors.forename: Moran
authors.initials: M
authors.lastname: Ben-Ziv
authors.forename: Liat
authors.initials: L
authors.lastname: Genosar
authors.forename: Lior
authors.initials: L
authors.lastname: Cohen
mesh_terms: D004058:Diffusion; D031541:Fluorescence Resonance Energy Transfer; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D008958:Models, Molecular; D017510:Protein Folding; D011522:Protons
chemical_list: D011522:Protons; D049452:Green Fluorescent Proteins