Whats in ocean water?
R. Monastersky When a team of oceanographers used state-of-the-art techniques to analyze seawater, they came to a surprising conclusion: Tattered remnants of bacteria constitute much of the dissolved matter in the open ocean. This finding adds to a growing appreciation of bacteria’s role in the seas. “Bacteria are seen as more and more central to every aspect of what’s going on in the open ocean,” says Matthew D. McCarthy of the University of Washington in Seattle. McCarthy and his colleagues collected thousands of liters of water from remote spots in the central Pacific, the Gulf of Mexico, and the North Sea. They pumped the water through a series of filters, the last of which were so fine that they sifted out individual biological molecules—material collectively called dissolved organic matter. The oceanographers focused on amino acids, the building blocks of peptides and proteins. They found that four of the amino acids in the dissolved matter appeared in two flavors, left-handed an
