Ruth Nussinov

Ruth Nussinov (Hebrew: רותי נוסינוב) is an Israeli-American biologist born in Rehovot who was a professor in the Department of Human Genetics, School of Medicine at Tel Aviv University and is the senior principal scientist and principal investigator at the National Cancer Institute, National Institutes of Health. Nussinov is also the editor in chief of the Current Opinion in Structural Biology and formerly of the journal PLOS Computational Biology. She was elected a member of the National Academy of Sciences in 2025.

In 1978, Nussinov proposed the first dynamic programming approach for nucleic acid secondary structure prediction, this method is now known as the Nussinov algorithm.

Her most important discovery was in the 1990s. In 1999 Nussinov published the transformational concept that all conformations preexist—even if the crystal captures only one—and that evolution harnesses their dynamic interconversion for function, dispelling the dogma that only the wild-type shape is relevant. Nussinov suggested a vastly different scenario from the-then dogma of two, "open" and "closed" conformations proposed by Monod, Wyman, and Changeux. She proposed that there is not one folded form, nor two—as they suggested—but many different forms, and in equilibrium, the system keeps jumping between them, and that this barrier-crossing is function. The concept that she suggested is significant since it explained that rather than the ligand inducing a conformational change (as in induced fit), the ligand can select a preexisting (relatively rare, non-minimal energy) conformation in the system that may be better suited to dock it, with minor optimization. It will then bind the ligand, and the equilibrium will keep producing more of this conformation to compensate, which she suggested (also in 1999), is the allosteric effect.