How do bacteria avoid wasteful production of unnecessary proteins when their genes are always on? The answer lies in regulating the operon. As trp levels increase, trp binds to trpR, causing a ...

Last week I finally addressed promoters and gave a bit of background on the lac operon. Looking back, I feel that I didn't give the topic of operons adequate treatment. They are a very crucial aspect ...

Proceedings of the National Academy of Sciences of the United States of America, Vol. 70, No. 12, Part I (1973), pp. 3576-3580 (5 pages) The amino-acid sequence of lac repressor from Escherichia coli ...