IN MEMORIAM

IN MEMORIAM

David Stephen Sigman

Professor of Biological Chemistry

Los Angeles

1939—2001

David Stephen Sigman, an internationally renowned UCLA professor of chemistry and biological chemistry who invented "chemical nucleases" and illuminated the molecular mechanisms by which enzymes catalyze biological reactions, died at his home in Brentwood on Sunday, November 11, 2001. He was 62 years old and had fought a 2 1/2-year battle with brain cancer.

 

During his career at UCLA, Sigman published more than 130 research papers, was editor since 1988 of the highly respected reference series "The Enzymes" and taught generations of students how chemical reactions make life possible.

 

David was born on June 14, 1939, in New York City, and attended Oberlin College, where he graduated magna cum laude in chemistry in 1960. He went on to Harvard to do graduate work with Frank Westheimer, and received his Ph.D. there in 1965. After postdoctoral work with Elkan Blout at the Harvard Medical School, he served briefly as an instructor at Harvard before joining the UCLA faculty in the Department of Biological Chemistry in 1968.

 

Sigman's research was highly interdisciplinary and bridged the fields of organic chemistry, biochemistry and molecular biology. He was one of the founding members of UCLA's Molecular Biology Institute, serving as its associate director from 1994 to 2001, while serving as a professor in two UCLA departments: chemistry and biochemistry, and biological chemistry.

 

David Sigman created a new field of bioorganic chemistry when he discovered that complexes of small organic molecules with metals could mimic large enzymes in cutting DNA, the molecule that contains our genetic blueprint. Going against the grain of a field that increasing relied on large molecule catalysts, David realized that small complexes might be much more useful. By coupling proteins or small segments of nucleic acids to these metal complexes, Sigman created a new class of DNA cleaving agents and showed that specific gene sequences in DNA could now be cut at will. These molecular 'tools' form the basis for the development of new drugs, especially those that target cancer cells. David had no fear of going out on a limb in new areas of research. In his career he branched out from proteins to nucleic acids, from biochemistry to molecular biology to pharmacology and molecular medicine.

 

David was a terrific classroom teacher and university citizen. His course "Biological Catalysis" is fondly remembered by its students for its rigor, his dedication to molding young minds, and his great sense of humor. He took on much more than his share of university service, and took his responsibilities seriously - UCLA as an institution mattered to David and he did much to ensure that its democratic ways and tradition for fairness were not impaired.

 

Sigman received many honors and awards for his contributions to science, including being honored as an Alfred P. Sloan fellow, as a Josiah Macy Jr. Foundation Scholar and as the B. R. Baker Lecturer at University of California, Santa Barbara. He was active in scientific issues at the national level, having served on the Educational Affairs Committee of the American Society for Biochemistry and Molecular Biology and on National Institutes of Health Study Sections. He was also active in the local community, with such activities as sponsoring an outreach program for Los Angeles high school science teachers and serving as an officer in the local chapter of Phi Beta Kappa.

 

David was an extremely generous friend and mentor to his colleagues. He will be remembered as a large part of the collegial glue that held our biomedical community together. Everyone knew him as the guru for bioorganic chemistry and he was a dedicated mentor of younger scientists both here and elsewhere. He spent a great deal of time advising younger faculty and promoting older colleagues and often wrote letters on their behalf for promotions and prizes. David loved the Molecular Biology Institute at UCLA and had enormous admiration and affection for Paul Boyer, the MBI director. The MBI building at UCLA is called Boyer Hall for two reasons. Paul Boyer's accomplishments that include the 1997 Nobel Prize in Chemistry and David's doggedness and letter writing in persuading the UCLA administration to call it Boyer Hall for intellectual rather than economic reasons.

 

David thought the world of friends and colleagues but his family was his special world. This included his wife, Marian Diamond Sigman, professor of psychiatry and biobehavioral sciences and psychology at UCLA, his children Hilary Sigman, professor of economics at Rutgers University, and Daniel Sigman, professor of geosciences at Princeton University, his grandchildren (Merrick, Hana and Darcy) and his mother, Helen. He was so proud of Marian. His colleagues were entertained endlessly with stories of her scientific accomplishments, the grants she had just obtained, the trips she took to Africa and other places and the pride David felt as he often accompanied her on those trips. David adored and admired his children and was a devoted son to his mother.

 

It is fair to say that David's thoughtfulness and caring, wit and intelligence brought out the best in those around him. We are all a little less complete without him and will miss him terribly.

 

Steven Clarke

Michael Grunstein