Word: tatum
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Dates: during 1950-1959
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...half of the $41,420 prize goes to Dr. Joshua Lederberg, 33, of the University of Wisconsin and the other half to Drs. E.L. Tatum, 49, of New York's Rockefeller Institute, and George Wells Beadle, 55, of the California Institute of Technology...
...Beadle teamed up with Dr. Edward L. Tatum, a chemist now of the Rockefeller Institute, and selected a new laboratory victim, the so-called red bread mold (Neurospora crassa), which is really a beautiful coral pink in its natural state, unmolested by geneticists. Neurospora is a geneticist's dream. When properly introduced, it mates and reproduces sexually. It also grows nonsexually, so a truckload of mold with the same heredity can be grown, if desirable, from a single spore. But the best thing about Neurospora is that it asks for so little. It thrives on a medium containing nothing...
Mutated Mold. The Beadle and Tatum plan for Neurospora was to try to create strains that differ from the normal mold in simple, chemical ways. Their method was simple, too. They irradiated mold with X rays to induce mutations. Then they gathered spores formed by sexual reproduction and laid them out on a sheet of agar jelly containing the minimum nutrients that natural wild mold requires. Some of the spores sprouted and grew normally, showing that they had not been mutated in any obvious way. Some were dead, perhaps mutated too much...
...start of the experiment, Beadle and Tatum resolved to make at least 1,000 tries before giving up. Such perseverence was not necessary. On the 299th try they found an ailing spore that needed only vitamin B-6 (pyridoxine) to make it grow lustily. When it had mated with a normal mold, it transmitted its need for vitamin B-6 to its descendants in the proper Mendelian manner for a single mutated gene...
...Attitude. When Beadle and Tatum reported their success in 1941, they had quite a collection of defective molds, each needing some extra nutrient or having some other gene-controlled chemical ailment. In a few years their imitators filled their own laboratories with molds as unnatural as the most monstrous fruit flies. The coral fluffs of normal Neurospora are rare in the test tubes and Petri dishes. In their place are blackish warts, lichenlike incrustations, or sick-looking globules. One horrible kind of mold grown in a moving liquid floats in bunches with limp limbs like soft, dead crabs...