Genetics Department
University of Wisconsin
Madison, Wisconsin

December 15, 1953

Dr. K. B. Rogers
Children's Hospital
Birmingham

ENGLAND

Dear Dr. Rogers:

With the collaboration of Dr, Aleck Bernstein (currently on leave
from the Public Health Laboratory Service) we are looking into the
possibility of extending genetic analysis to the serological types of
Escherichia coli that have been implicated in infantile diarrhea,

We have so far found a single strain of the 0-55 type that appears to
be crossable with other E. coli strains but a proper analysis will re-
quire somewhat more extensive material than we have at our disposal,
In order to avoid umecessary duplication of effort, it seemed to us
that it would be profitable to confine our initial screening tests to
a single strain of a given cultural or phage type. Dr. Bernstein sug-
gested that you might be in a position to provide a series of type
cultures of the serotypes 0-55, 0-111 and 0-26, in particular the type
cultures for the different lysotypes that are now being worked out.
Our primary concern is to collect a group of cultures for detailed
genetic comparison, among which we can hope that there is as little
duplication as possible. We would be indebted to you for any assistance
that you can give us.

I would also greatly appreciate receiving reprints of your publi-
cations on these organisms,

Yours sincerely,

Joshua Lederberg,
Associate Professor of Cenetics

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