OLS ELLE RATAN A AUER NAb ip tegen an tene = Set  ey g oe

November 11, 1953

Dr. P. D. Skaar
Biological Laboratortes
Gold Spring Harbor
Lon; Island, New York

Dear Dave:

I hope everything is going well with you at Cold Spring Harbor. Tracy,
as well as myself, has been conserned not to have heard from you since you
left the Midwest. I trust this is a sign of distraction rather than difficulty.

_ I want to check with you about a detall on the behavior of £. sold, line
28, mentioned in your reports. In Table 1 of one of your sumartes which
reviews the over-all behavior of lines 1 to Jl, line 28 is rceorded as being
not only ss but also motile in three out of three trials. This does not
quite agree with our present experience; that 1s, I have not yet been able
to obtain a motile derivative of the line 28 that we are now using. 4s there
has been, however, some confusion in the designation of thig partioular line
it is possible that you were using a slightly different strain. Do you have
any other details on this vearticular experiment?

Aleck Bernstein has been occupying hinself with the chemical properties
of the flagella of different Salmonella types. It has been possible to com
firm the old observation of Sertic that phase IT flagella are generally agelut-
inated by acriflavine whereas pase I flagella are not. This shows up not only
in the agulutination of the intact bacteria but also, so far as current
iments indicate, to the isolated flagella as well. We are setting out to do
somewhat more detailed physical-chemical compurisons of this matertal. The
difference of inagglutin ability of the difforent phases appears -to be quite
general, All of the phase I flagella that have been tested are inagglutinable
while all of the phase IZ flagella are agglutinable. This eoncords rather
nicely with the bi-local determination of these complexes. Aleck and [ether
have also verified the crossability of a mmber of 0-55 strains. They are,
however, only just now about to mke serclogical determinations.

As you may Inow, Ielen Byers came back fron Europe this summer a bit late
but also carrying with her an amebie infection. This has been cleared up,
however, and she ig busily engaged tn her classes and 4n sone research.
Letter to r. D. Skaar - Page 2 ; November 11, 1953

I an just about to finish a comprehensive experiment on the exper~
inental production of incompatibility by transfer 4n motility medium. Twenty
separate colonies of 581GL were carried for two passages in tubes or plates
of notility medium. Fourteen of the twenty isolates were F-. Of the re~
maining six, one appears to have an exhalted F+ status — a result which had
been noticed before, while most of the remainder appeared to be either like
58161 or relatively, but not completely, sterile. These isolates will be
tested through additional passages in motility medium. In addition, the
first passage strains will be cheoked to determine what proportions of the
strains had already become F- at that time.

I hepe to hear from you and what you are doing before this work is
completed. At that time, however, I will return the draft mamscript of |
the paper on this subject, which I think should be prepared for publication
before too mich more time passes. .

I am looking forward to hearing from you in the very near future.

Yours,

Joatma Lederberg
/me