is Edward Tatum's birthday. Tatum was an American biochemist who discovered with another American geneticist, George Beadle, that chemical processes in organisms are controlled by the organism's genes. These processes can be separated into distinct sequential reactions where each reaction would be controlled by one gene. They also discovered if a single gene mutates, the corresponding chemical reaction would change. This led them to propose the "one gene-one enzyme" hypothesis.
Tatum also discovered with Joshua Lederberg that bacteria can reproduce sexually through genetic recombination. Their work is used to provide information on genetic controls of the cells biochemical processes.
These two discoveries would earn all three men the 1958 Nobel Prize in Medicine. Find out what else occurred on this day in science history
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