Discovery
The lac repressor was first isolated by Walter Gilbert and Benno Müller-Hill in 1966. They were able to show, in vitro, that the protein bound to DNA containing the lac operon, and released the DNA when IPTG was added. (IPTG is an allolactose analog.) They were also able to isolate the portion of DNA bound by the protein by using the enzyme deoxyribonuclease, which breaks down DNA. After treatment of the repressor-DNA complex, some DNA remained, suggesting that it had been masked by the repressor. This was later confirmed.
These experiments confirmed the mechanism of the lac operon, earlier proposed by Jacques Monod and Francois Jacob.
Read more about this topic: Lac Repressor
Famous quotes containing the word discovery:
“The gain is not the having of children; it is the discovery of love and how to be loving.”
—Polly Berrien Berends (20th century)
“It was one of those evenings when men feel that truth, goodness and beauty are one. In the morning, when they commit their discovery to paper, when others read it written there, it looks wholly ridiculous.”
—Aldous Huxley (1894–1963)
“There is a great discovery still to be made in literature, that of paying literary men by the quantity they do not write.”
—Thomas Carlyle (1795–1881)