Wilfred Stein

As a visiting scientist at the University of Copenhagen in 1993, Stein worked with the Danish physiologist Thomas Zeuthen on the coupling of water and substrates in membrane proteins. They provided a conceptual framework for how a flux of substrates through a membrane protein can lead to a co-flux of water. Zeuthen & Stein suggested that the substrate-flux generates a hyperosmolar compartment within the protein, i.e. in the aqueous cavities abutting the outer solutions. As a result, water enters this compartment by osmosis and proceeds across the membrane.

Conceptualization and mathematical modeling of how membrane channels, carriers and pumps work to transport molecules across the cell membrane. Stein was the first to propose a model of the cell membrane as a fluid, amphiphilic structure. He presented this idea at the Society of General Physiology meeting in 1968, where the chairman of the session said: "Let’s stop here and discuss this interesting new idea" . Stein's model, however, was not as cogent as the fluid mosaic model some years later presented by Singer and Nicolson, who are credited with the idea in text-books.

Stein received his M.Sc. degree in 1954 in Physiological Chemistry from the University of the Witwatersrand, and his PhD degree from King's College London in 1958 in Biophysics. He did postdoctoral work in University of Cambridge UK and University of Michigan Ann Arbor, before taking up a position as Assistant Professor at the University of Manchester UK (1963–1968). He moved to Israel in late 1968, joining the faculty of the Alexander Silberman Institute of Life sciences, Hebrew University of Jerusalem in 1969, where he remained until his retirement in 2006. He taught biochemistry, biophysics and physiology. He also taught at the Weizmann Institute in Israel, where he continued as a consultant through 2003.

Wilfred Donald Stein was born on 26 November 1931 in Durban, South Africa to Philip, a mathematician, and Lily (née Rolnick) Stein. His parents emigrated from Lithuania as young children. He was the third of his siblings, Sylvester Stein (born 25 December 1920) and Zena Stein (born 7 July 1922). Wilfred Stein attended the University of the Witwatersrand (Wits), Johannesburg SA, receiving his MSc degree in 1954 based on his thesis "Melanogenesis and the structure of the melanin granue." In 1954, he married Chana Morgenstern, born 27 October 1934, before leaving South Africa to study in London, UK. They had four children, Aryeh David (b. 1956), Moshe Baruch (b 1960), Gideon Paschal (b. 1962) and Rebecca Miriam (b. 1966). He has 9 grandchildren.