WASHINGTON        .UNIVERSITY

DEPARTMENT OF MICROBIOLOSY
EucLlD AVENUS AND KIN~sH~~HwAY

SCHOOL OF MEDICINE
BAINT   LOU18

March 25, 1955.

Dr. Joshua Lederberg
Department of Genetics
University of Wisconsin
College of Agriculture
Madison 6, Wisconsin

Dear Josh:

     I want to thank you for the delightful visit I had with you,
and regret for my sake that it was so brief.  If I ever have the oppor-
tunity to get away from the things that I sm doing, I will certainly
head in the direction of microbial genetics.

     Irving Crawford had determined prior to the receipt of your
letter that WG35 is the &&j&type, and was able to show that it does
contain an amount of uracil condensing enzyme comparable with that
which is found in the uracil-less mutant.

    1,~ sending you a sample of erotic acid (several grams) and
thymidine (100 mgms.) which I hope you will put into your elixirs when
you are mutant hunting.  I will be very appreciative if you will let
me know if you have any success with them.

With best regards and thanks for your generosity,

Sincerely,

AK/M&

Arthur Kornberg.