More important, he changed the culture at the journal, bringing in more scientifically trained people to evaluate and edit papers, encouraging more news coverage and actively soliciting scientific reports.
Koshland said he was surprised to find that most of the journal's editors had backgrounds in writing, not science. Previous editors had hoped to improve the journal by improving the quality of the editing. Koshland decided to improve it by being more selective of articles and improving the quality of submissions.
By the end of his tenure, only one in every 10 submissions was chosen for publication.
His emphasis on scientific news made the journal a "must-read" not only for researchers, but also for stockbrokers, businesspeople, legislators and their staffs. "All I have to do is say something unflattering about a congressman and I get a phone call from him," he said.
Daniel Edward Koshland Jr. was born in New York City on March 30, 1920. His parents were banker Daniel E. Koshland and the former Eleanor Haas, cousins who were both heirs to part of the fortune of Walter Haas, founder of Levi Strauss & Co. The family moved to San Francisco two years later when the senior Koshland joined the company, eventually becoming vice president, president and chairman during his 57-year tenure.
Koshland recalled his childhood as "a landscape of boredom from sea to shining sea." There was, he said, none of "the material that generates good novels: no broken homes, no misunderstood childhood, no criminal youth gangs, no disastrous liaisons."
His interest in science was sparked in the eighth grade when he read "Microbe Hunters" by Paul de Kruif and "Arrowsmith" by Sinclair Lewis. Fascinated, he took all the courses in science and mathematics available at his high school.
Enrolling at Berkeley, he majored in chemistry. One insight into his character was provided in an inorganic chemistry course taught by Wendell Latimer. Koshland had just finished a final when Latimer asked him if an A in the course would be sufficient because Koshland already had aced three previous exams.
As Latimer prepared to tear up his test, Koshland "reacted angrily," pointing out that he had studied hard for the exam. "You owe it to me to correct it," he told Latimer. He got his A.
Koshland received his bachelor's degree in 1941 and went to work for the Shell Oil Co. in Martinez, Calif. When World War II broke out, he tried to enroll in the Navy but was rejected because his eyesight was 20/400, making him "legally blind" as far as the Navy was concerned.
Shortly thereafter, he received a call from Latimer, inviting him to move to Chicago and join a mysterious venture known as the Manhattan Project, telling him that the work was "the most important job in the world." Koshland spent the bulk of the war in Oak Ridge, Tenn., purifying plutonium for the world's first plutonium-based atomic bomb.
While he was at Chicago, he met Marian Elliott, whom he affectionately called Bunny. They married in 1945 and were devoted to each other until her death from lung cancer in 1997.
After the war, he returned to the University of Chicago to earn his doctorate in biochemistry, graduating in 1949.
By the 1970s, his interests had turned from enzymology to the study of how bacteria respond to their environment, a response called chemotaxis. He thought that would be a simple type of memory that could be studied biochemically and genetically.
He showed that bacteria have a rudimentary form of memory that allows them to compare past and present, and he demonstrated that they detect chemicals in their environment by means of receptors on their exterior. These receptors, he discovered, are linked to molecules on the bacteria's interior that transmit the signals and change the organism's behavior.
More recently, he turned his attention to the emerging field of bioenergy, looking into the use of cyanobacteria to produce methane as a fuel source.
"Unlike most scientists at his stage of career, he showed a striking willingness to switch directions and tackle new fields with creativity and originality," Tjian said.
In 1998, he received the Albert Lasker Award for Special Achievement in Medical Science in recognition of his lifelong contributions to medical science. The Lasker award is often considered a precursor to the Nobel Prize. He received a wide variety of other awards as well.
After Marian's death, he reconnected with Yvonne Cyr San Jule, whom he first met in 1940 when they were undergraduates in a Berkeley bacteriology course. They were married in August 2000.
In addition to his wife, Koshland is survived by two sons, James of Atherton, Calif., and Douglas of Baltimore; three daughters, Ellen Koshland of Melbourne, Australia; Phyllis Koshland of Paris; and Gail Koshland of Tucson; two sisters, Francis K. Geballe of Woodside, Calif., and Phyllis K. Friedman of Hillsborough, Calif.; nine grandchildren and one great-granddaughter; three stepchildren; 12 step-grandchildren and 17 step-great-grandchildren.
A campus memorial service is planned for the fall.