25 June 1958

Professor E, Toenniessen
Friedr, Naumannstr, 15
Kassel

GERMANY

Dear Profess or Toennisssen:

Thank you very kindly for your letter of June 7, aml for the
enclosed mss, and reprints,

Unfortumtely, I am making preparations for extensive travel
for the summer, and it would be very difficult for me: to give your
ms, the attention it deserves, especially as my reading of German is
somewhat more-time-consuming than in English. TI will be looking forward
to reading the reprints of your earlier papers, as I have a special interest
in earlier thinking about the genetics of bacteria,

You refer to the possibility of $ransplanting the gene complex of
capsulated to non-capsulated bacteria, This is, of course, the substance
of the original work on the ‘pneumococcus transformation! by Griffith,
followed by the more extensive studies of Hotchkiss, Ephrussi-Taylor and
others, There is also one claim for the same phenomen in K, xmemem pneumo-
niae by Ciantini (19h, Boll. ist. sieroter, Milan, 23, 47) but I must
confess to being rather sceptical of the details. Falows et al. (1955,
Jour, Bacteriol., 69, 139, "Attempts to demonstrate type transform: tion
with K. pneumoniae") had completely negativeresults but they did not take
advantage of the most modern methods. I have no doubt whatever that the
systematie application of current techniques to this group of bacteria
would generate the same successes as have been achddéved with the relgsed
genera of Escherichia and Salmonella, Together with your ms., which I
am returning unier separate cover you will find a recent review that touches
upon these questions. Like yoyrself, I originally thought that phenomena
like the pneumococcus transformation spoke for cyteplasmic factors, but
have been obliged to change my view in the face of later evidence,

At the present time, the most convincing examples of cytoplasmic induction
are to be found in yeast, with respect to the respiratory factors which can be
removed by treatment with acriflavine and restored by cytogamy with normal

cells, In bacteria the only nearly convincing examples are the factors con-
trolling male competence and eolicin synthesis in E. coli.

May I suggest that you communicate with your compatriot, Dr. Richard
Kaplan , Mikrobiologisches Instatut der Universitat Frankfurt a.™, » who is
one of the most active German workers on bacterial genetics at the pre-
sent time. I should think that either the Ztschr, f, Vererbungslehre
or the Zbl, Bakt. would te appropriate vehicles for your remarks, but I
venture to suggest that they might be fortified by a correlation of
your work with what has been done on the pneumococeus,

Yours cordially,

Joshua Lederberg
Professor of Medical Genetics

MAS POL

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