FEDERAL SECURITY AGENCY
PUBLIC HEALTH SERVICE

 

IN REPLYING. ADDRESS THE

USPHS Tbe. Research Lab.
All Fast 69th Street

New York £3.

Dec. £9, 1952

Dr. Joshua Lederberg
Dept. of Genetics
University of Wisconsin
Madison 6, Wisconsin

Dear Joshua,

Thank you for your letter of Dec, 4th. After several rereadings I think I
understand the problem a little better and I am very glad that you are
willing to prepare the heterozygote while we prepare the stocks and do the
scoring. I think this is a very satisfactory arrangement; the only modifi-
cation I would suggest that if the experiments work out successfully it would
be desirable for pedagogic purposes to have Yaniv repeat the isolation of

the heterozygote according to your directions.

It will probably take some time before we can expect to be sending you
strains since Yaniy has just started to prepare an extensive series of
mutants with varying degrees and numberof steps of resistance. He will

then try to get an answer to the question of dominance, as well as the
question whether multi-step resistant mutants yield intermediate recombinant
progeny. In order to avoid complications that methionine adds to the scoring
we are not using 58-161 but are rather using one of Gordon Allen*’s stocks
that requires proline and histidine. This gives prototrophs very nicely
with 677, so a linkage map for the proline and histidine should be available
soone

Norton presented a staff meeting at the Inditute last week, The material,
of course, 48 beautiful but I'm afraid the presentation was rather too
condensed for the audience. It got me to thinking that it might be a good
thing for Norton and me to put out a brief note on the biochemical evidence
that the addition of a tryptophan requiremnt to the ty ph salmonella
did not involve the introduc @ block in another reaction, This
evidence could Gulp be prosented briefij¥by referring to a paper on the
accumulation of shikimic acid derivatives and since this paper has just
been submitted to the J. Bact. I'll delay doing anything about a note until
the fate of this paper is settled. 4 - Tie ume’
LLL ssa A Meg Ge
I don't know whether I mentioned to you that I have been invited to veview
microbial genetics for the Annual Review of Microbiology next year, and
have asked Norton to share the job with me. I don't really feel equipped
to handle this topic if the title is taken seriously, even though the
editors invite selective rather than comprehensive reviews. With this
collaboration, however, it ought to be possible to handle the field better.
I finally got around to reading Plough's paper carefully, and have sent
him the enclosed letter. As yet there has been no reply. I don't think

you have to worry about the reference to my checking your strains as well
as his; this was introduced purely for diplomatic purposes.

Best wishes to you and Esther for the new year,

Sincerely,
Dp cyecce
BDD/em Bernard D. Davis
ol a a. ae , me
. i