OBITUARY: Christian Anfinsen

Christian Anfinsen was the joint winner of the 1972 Nobel Prize in Chemistry for work done with the enzyme ribonuclease while he was chief of the laboratory of chemical biology at the National Institutes of Health (NIH), at Bethesda, Maryland.

Anfinsen, with S. Moore and W. H. Stein (of Rockefeller University), received the prize for his contribution to clarifying relationships between structure and function in proteins. Anfinsen is also credited with the "Anfinsen dogma": that the amino acid sequence of a protein is sufficient to dictate the final three-dimensional structure, and thus the function of that protein in a given chemical environment. Known today as the "protein folding problem", it represents one of the most active areas of biochemistry and biophysics, and Anfinsen maintained a leading role in it to the end of his life.

Anfinsen remained active until the end, running a National Science Foundation- funded research project in his laboratory at Johns Hopkins University, Baltimore, where he was Professor of Biophysical Chemistry. His most recent research utilised enzymes from hyperthermophilic bacteria collected from the edges of tectonic plates from the floor of the Mediterranean Sea and the Pacific Ocean. He travelled world-wide to deliver lectures, to advise on research and humanitarian issues, and just for fun. He was an avid sailor, and on his last day in the laboratory, he was making plans to buy another sailboat.

While Anfinsen's contributions to the area of protein folding are well recognised, he was also a pioneer of ideas in the area of nucleic acid compaction, a fact that has entirely escaped recognition. In his book The Molecular Basis of Evolution (1959), a masterful and ground-breaking treatise on the linkage between protein chemistry and genetics, there is a paragraph in which he identifies the problem of DNA compaction and topology and it relation to chromosome physiology in terms that are timely even today. This chapter helped me to become a biologist and set me to work with the biophysics of chromatin.

Anfinsen was active in a number of advisory committees. He was a member of the Weizmann Institute Board, and of the Pontifical Academy of Sciences, and he belonged to the National Academy of Sciences (USA), the Royal Danish Academy of Sciences, and the American Philosophical Society. He gave numerous honorary lectures and was awarded several honorary degrees and medals, including the National Library of Medicine Medal. He published more than 200 original articles, mostly in the area of protein structure and function.

Anfinsen championed several humanitarian causes, including the responsible use of research and the prevention and/or elimination of weapons of mass destruction. In the late 1950s he led an NIH movement in support of the Linus Pauling petition against atmospheric testing of nuclear weapons. At that time, on the heels of the McCarthy era, it was "unwise" for federal workers to take part in such protests. Anfinsen threatened to resign his position if he and his colleagues were not allowed to sign this petition. The success of that campaign culminated in the signing of the Nuclear Test-Ban Treaty by President John. F. Kennedy in 1963. In 1984 Anfinsen was one of 55 Western scientists who volunteered to trade places with Yelena Bonner (the wife of Andrei Sakharov) so that she could travel to the West for medical treatment. She was subsequently allowed to visit Italy and the United States.

Anfinsen, of Norwegian descent, was born in Pennsylvania and received his undergraduate education at Swarthmore College, a master's degree in organic chemistry from the University of Pennsylvania, and a PhD in biochemistry from Harvard. From 1950 to 1981 he worked at NIH, retiring from what is now the National Institute of Arthritis and Metabolic Diseases. Next, he spent a year at the Weizmann Institute, in Israel, working on Interferon. In 1982 he joined Johns Hopkins University as Professor of Physical Biochemistry. There he taught both graduate and undergraduate courses and began his work with the proteins of hyperthermophilic bacteria. This new beginning coincided with the world-wide renewal of interest in the protein folding problem that he had first formulated in the late 1950s.

Behind all these bold scientific and public humanitarian actions was a gentle, almost shy personality. He was described by his wife of 15 years as "very easy going, but a man of great depth". I got to know him better when for the last several years we had almost regular afternoon discussions in his office covering such topics as sailing in the Chesapeake Bay; the principles of macromolecular organisation and the emergence of functional properties in them; the unfairness of human actions and the suffering of the innocent and the powerless; his letters of some years back to and from his then adolescent children; the poems of George Seferis, which I was translating for him from Greek; his plans for next week's experiment and how to help his struggling graduate students.

He seemed to have an enormous capacity for compassion, almost to a fault, which he preferred over the alternative. He admired beauty in all God's creations; in the sunsets at the Bay, on the faces of his loved ones, in the order and colour of the macromolecular assemblies we built on the graphics station in the laboratory. He was a gentle and sensitive man.

Evangelos N. Moudrianakis

Christian Boehmer Anfinsen, chemist: born Monessen, Pennsylvania 26 March 1916; Researcher, Carlsberg University 1939-40; professor, Harvard University 1941-50, 1962-63; Researcher, National Heart Institute 1950- 62, National Institute of Arthritis, Metabolism, and Digestive Diseases 1963-81; Visiting Professor, Weizmann Institute, Israel 1981-82; Professor of Biophysical Chemistry, Johns Hopkins University 1982-95; married 1941 Florence Kenenger (one son, two daughters; marriage dissolved 1978), 1979 Libby Shulman Ely; died Baltimore, Maryland 14 May 1995.