The waters of the Dead Sea, a landlocked lake between Israel and
Jordan, are the saltiest on Earth, inhospitable to all but a few
hardy species of bacteria and one species of alga. How do these
microbes survive? Researchers in Israel and the United States
have now found the secret of at least one of them. Haloarcula
marismortui (which means, roughly, salt- loving boxlike
bacterium that lives in the Dead Sea) has unique proteins that
protect it from the depredations of salt. To operate normally,
proteins must stay in solution, bonded to water molecules. Take
away the water, and proteins precipitate, binding instead to one
another and forming a whitish, dysfunctional sludge. A high
concentration of salts has that effect on most proteins: the
salts pull water molecules away from the proteins. In H.
marismortui, though, the proteins win the molecular tug-of- war.
Structural biologist Menachem Shoham of Case Western Reserve
University and his colleagues at Tel Aviv University and the
Weizmann Institute of Science