Processus photochimiques ultra-rapides: Du laboratoire aux systèmes photoactifs naturels

The UV-Vis subpicosecond absorption spectroscopy has been used to characterize and probe in real-time the primary photoinduced chemical processes in two photosensory proteins extracted from photomotile micro-organisms. This approach to the structure-function relationship of these photoactive proteins consists in comparing their photophysics to that of their chromophore isolated in solution, in order to evidence the specificity of the natural chromophore-protein complex. It has been shown that the photoisomerisation kinetic and quantum yield of the chromophore of photoactive yellow protein (PYP) are controlled by the properties of the protein nanospace in which it is embedded, and also that the oxyblepharism binding protein (OBIP) undergoes photoinduced picosecond reactions.