THE UNIVERSITY OF WISCONSIN
COLLEGE OF AGRICULTURE

Madison 6

DEPARTMENT OF GENETICS Sept. 25, 1953

Dr. R.D. Dawes

The “gkeht -Fleming Inst. of Microbiology
St. Mary's Hospital Med. School
Paddington, London, W.2

ngland

Dear Dr. Dawes,

The reference you requested is : Lederberg, E.M. and J. Lederberg
Genetics studies of lysogenicity in Escherichia coli. Genetics 38:51-64.1953, and
will be forwarded to you. +677 was not used #9 here, is not known to carry Gal 4,
and in fact carries a complex of factors resulting in a slow-fermenting phenotype,
and a heterogeneous progeny . witha baerGerk err tebe ion. 2pm The
Lac,-Mal]- strain two sublines were obtained independently: W-677 which is Mtl-Xyl-
ArabSl y.? Lp." and W-945 which is Gal- (unknown as yet® and in process of genetic
test) which is essentially the same except that the markers were independently
produced and may or may not be allelic with Wak those of W-677.

We are indeed tery much interested in #pctors” nked te*Gal and would
appreciate a few details of your norle resis tahee \ipves tigations. You remarked
that your culture of W-677 was not ij ntic sth the one used by Cavalli, but

Snagit