March 9, 195)

Dr. Norton Zinder

Rockefeller Institute for Medical Research
66th Street and York Avenue

New York ay,

New York

Dear Norton

This is to acknowledge your letter of March 1 ami to anawer your
question on the places where our presentations for Oak Ridge might overlap,
The report that I sent you is pretty much of a preliminary outline of what
I had in mind to say, though of course I would be relieved of the burden of
much general explanation of transduction on account of your own remarks,

You should, of course, feel free to draw as you please on any work that has
been cublished to the fullest extent necessary for you to develop your own
e@ygment. I do not think either of us has to be too deeply concerned about
duplication, The purpose of these discussions is to develop not a unified
party line but to bring out different viewpoints, sometimes on much the same
eete of facts, In my talk I am therefore planning to qo into some detail
about recent developments in Kel? and also to discuss those aspects of
Salmonella that are touched upon in the report, but not if I can help it

to restate the peneral and historical background of that work, for which I
am relying upon you, I am also hoping to give a general sort of perspective
on recombination mechanisas in general, tying together ani contrasting the
Salmonella and eoli stories. .

The single-cell studies on abortive transductions are turning out te
ve quite interesting. There is a pattern after all in their behavior, which
I think reflects a distribution of polytenic parte rather than an irregular
replication of the transduced piece,

Might I at this time suggest a reconciliation of terminology that might
help to eliminate some somatic confusion in transduction, To my mind trans-
duction has been defined to cover all of the related phenomena whether
mediated by phage or by extracted DNA.

It should be remembered, however, that tranaduce means transfer and
one should not therefore refer to the transduced cell, I see no objection
to referring to the altered cell as having been transformed, the otherwise

vague meaning of this term having been by this time defined by the context
of the discussion.

In connection with your nutrition pro vlem, I contime to be somewhat
struck by the nonespecificity of the effective primary challenge. This
makes one wonder if it is not related to the general alarm reaction, Have
you tried such experinente as using treatment with cold or subelethal doses
of, for exauple, formaldehyde as the primary challenges two or three days
Page 2 — Letter to Norton Zinder March 9, 195)

before the secondary challenge with virulent Salmonella? The response seens
altogether too prompt and too nonspecific to be of the usual antibody type,

Norton, I am afraid you are up to your old tricks again, and I must admit
that I could not follow many of the summary ccuments that you made on your
transduction work, If I were not looking forward to seeing you at Oak Ridge,

I would ask for a more straightforward explanation of your ehloromycetin effect.

If I might sumsarise the way in which our prospective talks at Oak Ridge
are likely to differ, it might be that you seem to be more preoccupied with
the initial stages of the traneduction process, the way in which the bacterial
genetic material gets into the bacteriophage, while the burden of my remarks
will concern the terminal stages, the implantation of this material into the
recipient genotype.

Yours sincerely,

Joshua Lederberg
JL fag