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(2° E. A. Evans, Jr.

THE UNIVERSITY OF CHICAGO

CHICAGO 37° ILLINOIS
DEPARTMENT OF BIOCHEMISTRY
May 11, 1954

Dr. Joshua Lederberg
Department of Genetics
University of Wisconsin
Madison, Wisconsin

Dear Dr. Lederberg:

You will remember that you were good enough to furnish
us with the lysogenic strain of E. coli Kj9, together with its
indicator strain W1485. Doctors Mackal and Koppelman have been
using these in work on the physical-chemical characteristics of A
and for studying the biochemistry of the induction period. I
understand that there is an F” strain of Kyo which is non-lyso-
genic, and if you have such a strain, we would greatly appreciate
a slant of it. Our idea would be to use this as a control organism
and we would also like to attempt lysogenization of such a strain
with labeled ,. We would appreciate any comments or information
that you might have.

With best personal regards to you and to your wife, I am

Sincerely yours,

E44 bou.s

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