Federal Councillor Pascal Couchepin held a reception in Bern on Thursday 7 September 2006 for the winner of this year’s Marcel Benoist prize: the ETH Professor for the X-ray Crystallography of Biological Macromolecules, Timothy J. Richmond. The American scientist, who has taught and researched at ETH since 1987, is awarded the honour for his contribution to elucidating the structure of nucleosomes, the basic building blocks of chromosomes. (1)

Couchepin, who is Chairman of the Marcel Benoist Foundation, entertained Timothy J. Richmond at lunch in Bern to mark the announcement. Other members of the Board of Trustees of the Foundation, ETH President Ernst Hafen and various media representatives attended the reception. The official prize-giving ceremony will take place at ETH tomorrow, 15 September 2006 in the context of the 5th NCCR Congress on Structural Biology. (2)

In a short speech, Pascal Couchepin praised Richmond’s tenacity and imaginativeness. He said the researcher had shown great stamina and had always believed in his ideas, and ultimately these had also proved correct. Timothy Richmond said he felt honoured. However, he said modestly that the elucidation of the structure of nucleosomes was only an intermediate step. Research into these structures was still incomplete. He said science was like mountain climbing. When one peak had been conquered, the next was waiting behind it. He and his team are now researching the structures of the next organisation level of nucleosomes.

ETH President Ernst Hafen (l.) and Federal Councillor Pascal Couchepin (r.) in conversation with Timothy J. Richmond, this year’s Marcel Benoist prizewinner.

Despite all the researcher’s modesty, his structural analyses are regarded as exceptional. They really create the basis for an analysis of the functioning of nucleosomes at an atomic level. The discoveries about their structure are so fundamental that they have been incorporated into biology textbooks.

The structural analyses are based on the X-ray diffraction technique. This involves passing X-rays through a crystal lattice where they are deflected and generate a specific pattern. Scientists draw conclusions about the crystal structure from this. However, large molecular structures are very difficult to crystallise.

Richmond worked for thirteen years before achieving success with the nucleosome. Obtaining homogeneous nucleosomes from living cells is a particularly difficult problem. This is because they are not rigid immutable structures. Their components interact with their surroundings constantly in order to ensure the functioning of a cell. However, X-ray structural analysis needs crystals of suitable quality and size.

Richmond avoided this problem by building copies of nucleosomes in his laboratory from homogeneous components consisting of artificial DNA and histones prepared by genetic engineering. However, the fact that a great deal of astuteness and persistence lay behind his research remained largely unrecognised, since there was often a lack of results that would have been publishable in major scientific journals. Nevertheless he himself never gave up, nor were his sponsors discouraged from financing the research. Richmond stressed that ETH in particular had never refused him their support.

Building up an appropriate specialised infrastructure also made a decisive contribution to the success. To analyse complex macromolecules it is necessary to be able to generate X-rays of unusually high intensity and quality. This is why for about 20 years Richmond and his team have used synchrotron radiation of the kind that can now also be generated at the Paul Scherrer Institute in Villigen. Richmond said that the SLS (Swiss Light Source) was among the world’s best instruments and had advanced the work greatly. His team works with the SLS at least once a month.