Time-dependent density-functional approach for biological chromophores: the case of the green fluorescent protein.
We performed first-principles calculations of the optical response of the green fluorescent protein (GFP) within a combined quantum-mechanical molecular-mechanics and time-dependent density-functional theory approach. The computed spectra are in excellent agreement with experiments assuming the presence of two, protonated and deprotonated, forms of the photoreceptor in a approximately 4:1 ratio, which supports the conformation model of photodynamics in GFP. Furthermore, we discuss charge transfer, isomerization, and environment effects. The present approach allows for systematic studies of excited-state electron-ion dynamics in biological systems.
Marques
Miguel A L
MA
Departamento de Física de Materiales, Facultad de Químicas, UPV/EHU, 20018 San Sebastián, Spain.
López
Xabier
X
Varsano
Daniele
D
Castro
Alberto
A
Rubio
Angel
A
D000838:Anions; D003198:Computer Simulation; D049452:Green Fluorescent Proteins; D007536:Isomerism; D008164:Luminescent Proteins / Q000737:chemistry*; D008958:Models, Molecular; D010777:Photochemistry; D011487:Protein Conformation; D011789:Quantum Theory
D000838:Anions; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins