Renowned Molecular Biologist Dies

Alexander Rich, discoverer of Z-DNA, the RNA-DNA double helix, and the structure of collagen, has passed away at age 90.

May 6, 2015
Kerry Grens

DONNA COVENEYLong-time MIT biologist Alexander Rich died last month (April 27) at age 90. His scientific contributions were fundamental to understanding the structure of DNA, RNA, and other components of the cell.

“I can think of no one else who has made as many major contributions to all facets of modern molecular biology,” Robert Gallo of the University of Maryland School of Medicine told The New York Times.

Having trained with Linus Pauling, James Watson, and Francis Crick during the 1950s, Rich’s career centered on working out the structural configurations of DNA and RNA. In 1960, as a new professor at MIT, Rich demonstrated that DNA and RNA could pair up. Years later, he took advantage of X-ray crystallography to prove the double helical structure of nucleic acid molecules and the shape of several RNAs, including transfer RNA.

In 1979, Rich and colleagues reported the discovery of left-handed DNA (as opposed to the conventional right-handed double helix), also known as Z-DNA. “After the initial discovery, many labs set out to understand the biology of Z-DNA, which turned out to be a much more difficult endeavor than discovering the structure in the first place,” Thomas Schwartz, an MIT professor who worked on Z-DNA as a graduate student in Rich’s lab, said in a statement. “While we still do not fully understand its biological role, the work on Z-DNA emphasized perhaps more than any other single piece of data how important the three-dimensional conformation of DNA in the context of the cell is.”

Rich’s contributions extended beyond the lab to industry; he cofounded the biotech companies Alkemes and Repligen. “Everybody thinks of Alex as a great scientist, and no doubt he contributed greatly to the study of DNA,” Repligen’s CEO Walter Herlihy told Boston Business Journal. “But the thing that stood out to me was, Alex stood out as a mentor . . . he just inspired so many scientists.”

Rich is survived by his wife, four children, and seven grandchildren.