Here, Luria responds to an inquiry by Pardee, who--along with Francois Jacob and Jacque Monod--had just one year earlier shown
that the enzyme beta-galactosidase is induced by changes in culture conditions. It was the first example of negative control
of induction due to a repressor protein. This discovery set the stage for additional experiments that further delineated the
interaction of a regulatory protein with a site on DNA that controls expression of other genes. With this letter, Luria also
enclosed a copy of his 1949 article with Rene Dulbecco.
Number of Image Pages:
1 (53,207 Bytes)
1960-05-23 (May 23, 1960)
Luria, Salvador E.
Pardee, Arthur B.
University of California, Berkeley
Original Repository: American Philosophical Society. Library. Salvador Luria Papers
Reproduced with permission of Daniel D. Luria.
Reproduced with permission of the American Philosophical Society.
Medical Subject Headings (MeSH):
From Phage to Colicins, 1945-1972
Genetic Recombinations Leading to Production of Active Bacteriophage from Ultraviolet Inactivated Bacteriophage Particles
I am enclosing the data on inactivation of the ability to form B-galactosidase after UV on the transducing phage. The value
of erg min-2 on the abscissa is taken from the Slope of the T2 curve (see Luria and Dulbecco, Genetics Soc. Amer. 18:102,
1949), and may be off 20%. Curve 3 measures the slope of the linear rate of enzyme formation, from 90 to 240 minutes after
infection with HFT lysate of Pl lac exposed to various UV doses.
I regret to say that at this point the experiment on inactivation of the i+ locus appears to be completely negative, contrary
to the original appearances. We have used lysates with 0, 8, and 10 hits on the lac property (0, 400 and 500 seconds) and
used them to transduce the strain with the lac deletion (see curve 4). Up to now, 80/80 transductants are still i+ after UV
(50/50 i+ in the control). Of course, this result may have many interpretations.
I look forward to hearing more from you. With best regards,