Abstract
Light is an important environmental variable and most organisms have evolved means to sense, exploit or avoid it and to repair detrimental effects on their genome. In general, light absorption is the task of specific chromophores, however other biomolecules such as oligonucleotides also do so which can result in undesired outcomes such as mutations and cancer. Given the biological importance of light-induced processes and applications for imaging, optogenetics, photodynamic therapy or photovoltaics, there is a great interest in understanding the detailed molecular mechanisms of photoinduced processes in proteins and nucleic acids. The processes are typically characterized by time-resolved spectroscopic approaches or computation, inferring structural information on transient species from stable ground state structures. Recently, however, structure determination of excited states or other short-lived species has become possible with the advent of X-ray free-electron lasers. This review gives an overview of the impact of structure on the understanding of photoinduced processes in macromolecules, focusing on systems presented at this Faraday Discussion meeting.
Highlights
Recent developments in ultrafast spectroscopy, computational chemistry and in particular time-resolved crystallography have provided unprecedented and novel insights into the very early processes induced by photon absorption, which so far had been difficult to investigate
Each microcrystal yields a single diffraction pattern upon X-ray free-electron lasers (XFELs) pulse exposure before it is destroyed by subsequent damage effects, necessitating high throughput serial data collection, an approach called serial femtosecond crystallography (SFX)
Light-induced double bond isomerizations occur in the chromophores of various photoreceptors, including tetrapyrrole in phytochromes, p-coumaric acid in photoactive yellow protein, retinal in rhodopsins and 4-(p-hydroxybenzylidene) imidazolidin-5-one in uorescent proteins (Scheme 2)
Summary
Organisms have evolved photosensory proteins that sense most of the spectral region, enabling phototaxis or photoavoidance, allowing us to see, and providing clues to e.g. synchronize daily rhythms Understanding these processes has an impact on human health (melanoma, jet lag, photodynamic cancer therapy.) and on sustainable energy sources by inspiring photovoltaic systems that use solar energy to produce electrical current. Recent developments in ultrafast spectroscopy, computational chemistry and in particular time-resolved crystallography have provided unprecedented and novel insights into the very early processes induced by photon absorption, which so far had been difficult to investigate Taken together, this information provides a detailed understanding of how the early excited-state relaxation couples to the protein matrix and how protein dynamics shapes early photodynamics and the subsequent photochemical events. It will be interesting to see common themes and variations emerge
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
