The Accademia Nazionale dei Lincei and the Consiglio Nazionale delle Ricerche promote an International Conference on the Biophysics of Photosynthesis, to be held in Rome, Italy, from 28th to 30th October 2013.
The photosynthetic process, present in plants, algae and some bacteria is the fundamental process which has permitted the development and maintenance of life on Earth. Light energy from the Sun is harnessed, via a complicated series of reactions, to synthesize covalent bonds between carbon atoms, where the origin of these atoms is atmospheric carbon dioxide. This biosynthetic process is massive, by far the greatest chemical synthetic process on Earth, and leads to the fixation of about 120 gigatonnes of carbon per year, at a global level. In plants the light is absorbed primarily by chlorophyll molecules organized in structures, known as photosystems. Each photosystem consist of 200-250 chlorophyll molecules, bound to membrane proteins, and carotenoid molecules that have fundamental antioxidative functions. The energy absorbed by these antenna molecules is transferred, on a picosecond time scale, to the small number of reaction centre chlorophylls, where primary photochemistry occurs by means of the transfer of an electron to a primary electron acceptor. This process, known as primary charge separation, is the first reaction which leads, via a complex electron transport chain, to the production of the chemicals (ATP, NADPH) necessary for carbon fixation.
The elucidation of these processes over the last century has been made possible by the close interactions between scientist with different backgrounds such as chemists, physicists and biologists. This strong interdisciplinary approach, which has always characterized photosynthetic research, continues, to this day, to provide important and detailed information on this remarkable process. The present Conference will be largely dedicated to the biophysical aspects of photosynthesis and will bring together prominent scientists from all over Europe.
The interest of biophysicists in photosynthesis has traditionally, and it is still largely the case, directed towards the understanding of photosystem characteristics and function. These processes are of great biophysical and biological interest in so far as the quantum efficiencies of photochemical charge separation are extraordinarily high, varying, for plant photosystems, between 0.85 ( photosystem II) and 0.99 ( photosystem I). One of the main aims of the present Conference is to cast further light on the photophysical mechanisms which lead to these high quantum efficiencies. Another main topic will be the well described but, to date, less well understood at a detailed photophysical level, photoprotective mechanism, known as "non-photochemical quenching", which leads to a decrease in chlorophyll triplet formation which, via singlet oxygen, leads to harmful oxidative reactions.
The Conference will be organized around the following main sections:
- i) photosystems - primary processes (energy transfer, charge separation, primary electron transport)
- ii) chlorophylls and carotenoids - protein modulated structure and function
- iii) non photochemical quenching - photophysical mechanism and function
- iv) thermodynamics of primary processes
The Conference will consist of lectures by invited speakers and presentations from scientists active in this area of research.