Air Mail

YALE UNIVERSITY
OSBORN BOTANICAL LABORATORY
NEW HAVEN, CONNECTICUT

November 23, 1949

Dr. Joshua Lederberg
Department of Genetics

The University of Wisconsin
Madison 6, Wisconsin

Dear Josh:

An adequate answer to your last letter is indeed difficult, and I
will in a sense delay answering until I see you in New York, I believe you
read into my activities much more that is sinister than is truly warranted,
Indeed, competition with you in a sense hea not particularly occurred to me
Since we got started on coli from work with little bearing on your field of
interest. ‘hat we overlap to an extent reflects primarily the complexity
of coli and of adaptation. I could write an answer, but letters are suoject
to misinterpretation, which in turn leads to ill will. I suspect we can
rapidly iron out the questions you have raised and to everyones mutual
satisfaction orally over a spot of beer in New York. I was pleasantly sur-
prised to tind that you would indeea consicer me, and my poor lab, real
competition.

The reason for the preceeding remarks hinge simply around the fact
that you have staked out a tremenaous area, Obviously we cannot steer
entirely clear of it with K-12, since much of our serological work requires
purified enzymes and a knowledge of the physiology of adaptation. Indeed
with the mutants it is difficult to remain entirely clear of such an all-
inclusive field. ‘the serological differences need to be correlated with
enzymatic differences. Such information is as useful after all to you as
it is to us.

i realize full well the discomfort of having some one grab the
precise problem one has under investigation. That cuestion, however, I
don't believe rezily is involved here, in a riela as large as tnis. I can
assure you, though, that any strains you may send us will ve used only ror
the purpose of establishing any serological differences or peculiarities
they may exhioit, Further work that we might want to carry on with them
would depend upon the outcome of the serological work and upon discussion
with you,

Regarding the serclogical work--tnis nas been carried out by Gave
lester, Lester nas found that antisera from rabbits injectea with lactase
grown cells does not cirectly inhibit enzyme activity. The entivody can
apparently combine with the enzyme without aifecting its activity. However,
the enzyme-antibody complex can be precipitated by centrifugation under
conditions that the enzyme itself remains in solution. ‘this, in substance,
Dr. Joshua Lederberg
November 23, 1949
Page 2

is his technique. He finds as I wrote earlier, that antisera to glucose
grown cells does not display this efYect upon the enzyne, which is in agree-
ment with our e to finu lactase by our methods in such cells. Y-53
grown on glucose, we find similarly lecking lactase, yet antisera to such
cells has a detectable amount of what we call incorrectly, "antilactase."
Lester has found, by the way, that wrole celle are very much poorer than

are ground ceils in terms of the serological difrerences that I mamtioned.

with best regards,

NS bLawe