September 11, 1953

Dear ibiy:

Our aff&irs are beginning to become m-ordered following our trip
to San Francisco and back, mat moving into a new house, and the conven&%on
of American Biologists on campus.  We envy your attendance at the meetings
atRom-- you can be sure that the sole obstacle to our own was financial.
I am just getting back to work, though I think I shall be spending more
time this year on E. coli cytology than on Salmonella serology. There are
some loose$ ends on the latter, however, and at any rate I expect the
program to be continued in full force in Bernstein*s hands. His arrival
is expectid tomrrowb.  Mrs. EWford was obliged to cancel his reservation
in deference to some University rules for student houaiog. Howeverqi this is
probably all to the better as BorisRotmn has just rented a large apartmnt
and hopes to interest Bernstein in sharing it with him.

Thank you ever soramuch for your letters and materials received during
the summer.  I have just finished a brief look at the k phage, and find the
stock preparation itself to be a highly competent transducing phage with
either SW-666 #$ (Kauffaannfs @-4~.&8~ monophasic para'B) or O-901 as Fndi-
caters.  If nothing else, this has been the first meana of using S. typhi
as a transductional source, and has given fpr example:
            k
  S. typhi  --x SW-666:       XV V XII dt-

In w hands also, w preparation of k seems entirely free of bacteria.

The parat typing phage BAOR seems also to be competent in transduction,
but with a host range rather more limited than PLT22. A few plaques have
been noticed on some kuneendorf strains, and have since been seen also with
PLT-22. I am hot sure whether these might not represent contaainatiag
phagea. At any rate, I have not succeeded in demonstrating transductions
to any group C strains, nor in building up either of these phages to an
appreciable titre on them.   The 0 phages, 1,2, and 3 have also given
disappointing results having been teeted, in particular against a etrain
of S. typhi @-9Ollysogeniaed for k (and, as you say, thereby immune to
the 0 phage) as indicator. I hesitate to insist on any such negative results,
however, and further tests are in order.

  As you know, Dr. Felix has refused my casual request for the 'B1 typw
phages. I can fully appreciate this policy; at any rate it is of no great
immdiate concern. Ih due couraeR I will be happy to have them, when available,

   I was interested to see the protocols on the host ranga of tb
B phsges you kindly sent on July 16, I was lntmeeted in the frequency
of heterologous reactions, dspecially in group C. I wonder if it would
be too much of ah iapoaition to ask either for the specific strains
of cholerae suis (13&3);newport,PortoRioo; and fayed, or in addition
for the additional information as to which particular phage in the Pool 2
they are reacting with.  I suspect that these protocols reflect only the
occasional positive reactiona you encountered, and not necessarily all
the cultures and types bmdmd tested.   If you should have occasion to
test the reactions of divers Salmonellas with & I should also be interested
to hear of them: again, the reactions with bacterial strains outside the
A-ED groups would be of most inmediate concern. Finally, k has been
working so well that I womier whether you could be imposed on to send sons
of the other determinate phages (especially if serologically distinct) at


some future time convenient to yourself.

We were very pleased last weekend to enter&& Bill Hayes. He certainly is
the personable chap you described him to be, and we were happy to make this per-
sonal contact ~espec&ally as there have been soms entirely gratuitous attempts
to inject non-existent personal issues in this scientific controversy]. At least
at the instant, he agreed that the tidings on our diploids, e.g. that some of
these may show one segment eliminated from the F+ parent, an adjacent segment
from the F-, are essentially fatal to the notion of a pre-zygotic defect in the
gametes as he and Watson had previously propesed.  I am pleased to note that he
plans to continue efferts to isolate the F agent which, if successful, Amay allow
a decisive test of his vector hypothesis. Barring     the differences between
our theories are largely verbal. On our side, we      ad some encouragement in
cytological examination of Hfr x F- [possibly      you ao11y3 of the slides
showing what might conceivably be conjugation f      and Iamplanning to
spend some time to test thezu possible role of     gums in the mating process.

  Please give our best to
in a couple of weeks, after

CliVe-   '=f?&etter
     I hope to send o
things have,sai&+ed down. '11   to him (and Wo Bruce)

                                .~ 1L

/ \ `-`-
\Q      Sincerely,

Joshua Lederberg