title: Ultrafast Dynamics of a Green Fluorescent Protein Chromophore Analogue: Competition between Excited-State Proton Transfer and Torsional Relaxation.
abstract: The competition between excited-state proton transfer (ESPT) and torsion plays a central role in the photophysics of fluorescent proteins of the green fluorescent protein (GFP) family and their chromophores. Here, it was investigated in a single GFP chromophore analogue bearing o-hydroxy and p-diethylamino substituents, OHIM. The light-induced dynamics of OHIM was studied by femtosecond transient absorption spectroscopy, at different pH. We found that the photophysics of OHIM is determined by the electron-donating character of the diethylamino group: torsional relaxation dominates when the diethylamino group is neutral, whereas ultrafast ESPT followed by cis/trans isomerization and ground-state reprotonation are observed when the diethylamino group is protonated and therefore inactive as an electron donor.
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) - Kolkata , Mohanpur, West-Bengal 741246, India.
authors.forename: Tanmay
authors.initials: T
authors.lastname: Chatterjee
authors.affiliation: Ecole Normale Supérieure, PSL Research University , UPMC Univ Paris 06, CNRS, Département de Chimie, PASTEUR, 24, rue Lhomond, 75005 Paris, France.|Sorbonne Universités , UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Lacombat
authors.affiliation: Ecole Normale Supérieure, PSL Research University , UPMC Univ Paris 06, CNRS, Département de Chimie, PASTEUR, 24, rue Lhomond, 75005 Paris, France.|Sorbonne Universités , UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France.
authors.forename: Dheerendra
authors.initials: D
authors.lastname: Yadav
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) - Kolkata , Mohanpur, West-Bengal 741246, India.
authors.forename: Mrinal
authors.initials: M
authors.lastname: Mandal
authors.affiliation: Ecole Normale Supérieure, PSL Research University , UPMC Univ Paris 06, CNRS, Département de Chimie, PASTEUR, 24, rue Lhomond, 75005 Paris, France.|Sorbonne Universités , UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Plaza
authors.affiliation: Ecole Normale Supérieure, PSL Research University , UPMC Univ Paris 06, CNRS, Département de Chimie, PASTEUR, 24, rue Lhomond, 75005 Paris, France.|Sorbonne Universités , UPMC Univ Paris 06, ENS, CNRS, PASTEUR, 75005 Paris, France.
authors.forename: Agathe
authors.initials: A
authors.lastname: Espagne
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) - Kolkata , Mohanpur, West-Bengal 741246, India.
authors.forename: Prasun K
authors.initials: PK
authors.lastname: Mandal
mesh_terms: D004583:Electrons; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D011522:Protons
chemical_list: D011522:Protons; D049452:Green Fluorescent Proteins