The conversion of sunlight into energy takes place in a minute molecular factory, the photosynthetic reaction centre. This reaction centre is surrounded by so-called aerial complexes, which absorb the photons (light particles) of the sun and pass on the energy to the reaction centre – super-fast and highly efficiently. The aerial complexes are comprised of a protein called ‘light-harvesting complex II (LHCII)’. Because the light intensity in nature varies greatly, the plant's reaction to this phenomenon was investigated. It was already known that a plant is able to release excess energy in the form of heat, rather than pass this energy on to the reaction centre. After all, too much energy would damage the reaction centre.
Herbert van Amerongen, Professor of Biophysics: ‘Our research was focused on the charting of the molecular basis of the processes used by a plant to monitor the harvesting of light. It appears that the atomic structure of LHCII is able to change. In one instance, the energy is discharged quickly – within a billionth of a second – as heat; in another, it is discharged much more slowly, in order that the energy can be used by the reaction centre.
In biophysics, life processes and structures are studied and explained in physical terms. This is done by using advanced spectroscopic technology. This particular research was carried out using equipment from the MicroSpectroscopy Centre at the Dreijen. The chair group of Biophysics is especially interested in the dynamics and the function of biological processes. One of the research themes of the group is the plant’s response to stress, including light stress, or bright sunlight. Van Amerongen: ‘There is a lot to be researched yet in this area – and we will continue to do so.’
Van Amerongen is enthusiastic about the future of his group. His is thrilled that the number of trainee research assistants and students is increasing. ‘I was appointed professor less than three years ago. Members of the chair group are publishing in leading biophysical magazines and perform well on an international scale. However, three years is somewhat short a time to be able to take up a very prominent position. A little more time is needed for this. However, an article in Nature is very welcome, and may be able to contribute to it.’