Professor Jan Anderson FRS - Shedding light on photosynthesis
Professor Jan Anderson has made outstanding experimental and conceptual advances in the understanding of the molecular organisation of the photosynthetic membranes of higher plants and algae. Her distinguished research has been marked throughout with a series of significant discoveries, elegant experiments and hypotheses, particularly the molecular organization of the photosystems, their dynamic arrangement in photosynthetic membranes, the exquisite way chloroplasts respond to over stimulation by light and a unifying concept of photoinhibition. This far-reaching experimental research coupled with imaginative flair, provided a conceptual framework for understanding the function and structure of photosynthetic membranes at the molecular level. Her innovative concepts and research have led to important conclusions on the molecular mechanisms of light-harvesting, electron transport capacity and the light regulation of photosynthetic processes.
Why did the Society award this Fellowship?
Jans fundamental research deals with photosynthesis - the unique process that converts solar energy to chemical energy. Green plants take sunlight, carbon dioxide and water to make food and oxygen is released. The photosynthetic apparatus is located in membranes, but its processes were completely unknown when Jan first started her research. "Together with Keith Boardman, I fragmented photosynthetic membranes to get two fractions with different properties, and so proved for the first time that photosynthesis needed two light-powered, tiny molecular machines: photosystems I and II," says Jan. A sabbatical leave in Cambridge during 1973 coincided with the UK coal miners strike. With severe electricity restrictions, experiments were impossible and Jan retired to the perfect ivory tower at Newnham College to dream about how the photosystems were arranged within the membranes in plants. The result was a seminal article, replete with speculations galore, which ushered in the era of the molecular organization of photosynthetic membranes. "My passion has been to explain the dynamic molecular organisation of the photosystems within photosynthetic membranes, as a key to understanding their function and structure," says Jan. "Perhaps my most celebrated and initially heretical concept together with Bertil Andersson was to demonstrate that the plant photosystems are actually separated from one another and occur in different membrane domains."
How will this work help society?
Without the evolution of photosynthesis with its magical conversion of solar energy to chemical energy, life on earth as we know it would not exist. Photosynthesis not only supplies the main biological energy input into the living world, but also provides the oxygen we breathe. The splitting of water to oxygen, hydrogen atoms and electrons is the most demanding biological reaction known. "Understanding how this marvellous molecular machine splits stable water to oxygen and two hydrogen atoms may allow the molecular engineering of synthetic small metal-peptide complexes that can mimic plant photosystem II, and allow cheap solar energy-driven generation of hydrogen gas from water," explains Jan. Electrolysis of water yields hydrogen gas, but man-made electricity is very expensive. In addition, understanding how the most oxidising reaction of biology by photosystem II takes place in a fragile protein environment with minimal generation of lethal reactive oxygen species may be relevant to oxygen chemistry in animals and humans that causes genetic and cellular damage during ageing and often triggers debilitating diseases.
What are the current areas of research being investigated?
Although light drives photosynthesis, too much light is bad for photosystem II (which generates oxygen from water) and it is inactivated. Jan advanced a unifying theory for the molecular mechanism of photosystem II inactivation. "Now that refined structures of photosystem II are available I am considering how its exquisite design prevents its reaction centre from interacting with lethal reactive oxygen species formed when water is split," says Jan.
What attributes are needed for a successful researcher?
"The three main attributes required are an unflagging curiosity, enthusiasm, indeed passion, and a creative ability to think laterally," says Jan. "Of course, "no man is an island" and my fascinating exploration owes much to the many colleagues who accompanied me during my long photosynthetic saga." Jan believes she has been lucky to have worked in a golden age when opportunities for research were almost unlimited, and science was judged solely by its excellence. "Now the joy of discovery and thrill of creating hypotheses which I so enjoyed is often stifled with excessive research management and picking winners which are the death of creativity in basic research," explains Jan. "We need some basic research to provide the intellectual capital for successful applied research."
Professor Anderson was made a Fellow of the Royal Society in 1996