The Chromophore Structural Changes during the Photocycle of Phytochrome:  A Combined Resonance Raman and Quantum Chemical Approach

• Autores: Mroginski, Maria Andrea; Murgida, Daniel Horacio; Hildebrandt, Peter
• Año de publicación: 2007
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Phytochrome; Photoreceptors; FT-Raman; DFT calculations
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Phytochromes are sensory photoreceptors that, upon light irradiation, can be transformed between an inactive and an active state. The conversion is initiated by the photoisomerization of the cofactor, a linear methine-bridged tetrapyrrole, followed by conformational relaxations of the chromophore and the protein matrix that finally leads to the formation of the signaling state. To elucidate the underlying molecular processes, resonance Raman spectroscopy combined with quantum chemical calculations constitutes a powerful approach since it allows determination of the chromophore structure in the various states of phytochrome. On the basis of these studies, a molecular model for the photoinduced reaction cycle is derived. Phytochromes are sensory photoreceptors that, upon light irradiation, can be transformed between an inactive and an active state. The conversion is initiated by the photoisomerization of the cofactor, a linear methine-bridged tetrapyrrole, followed by conformational relaxations of the chromophore and the protein matrix that finally leads to the formation of the signaling state. To elucidate the underlying molecular processes, resonance Raman spectroscopy combined with quantum chemical calculations constitutes a powerful approach since it allows determination of the chromophore structure in the various states of phytochrome. On the basis of these studies, a molecular model for the photoinduced reaction cycle is derived.
Fil: Mroginski, Maria Andrea. Universidad Nacional de La Plata; Argentina
Fil: Murgida, Daniel Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina
Fil: Hildebrandt, Peter. Universität Göttingen; Alemania