UNIVERSITY OF SOUTHERN CALIFORNIA
UNIVERSITY PARK
LOS ANGELES 7

December 10, 1957

Dr. J. Lederberg, Chairman
Department of Medical Genetics
Genetics Building

University of Wisconsin
Madison 6, Wisconsin

Dear Lederberg:

Quite by coincidence we had just prepared a batch of Spirillum
cultures to send to someone else and there were some extras conven-
iently available. Under separate cover you will receive cultures of
S. anulus and S. serpens. The anulus is the most conspicuous but it
is somewhat unreliable in its growth responses. I would suggest the
serpens from the poihtiof view of ease of culture if it fits the rest
of the requirements. I doubt that S. lunatum would be satisfactory
for your purposes since it should be cultured in sea water. Perhaps
the easiest of all the Spirillum to grow is itersonii; however, this
one is quite small and might not fit into the "conspicuous" category.
5. volutans would be ideal from the point of view of motility and
conspicuousness; unfortunately, although I succeeded in getting it in
pure culture last Spring while at Pacific Grove, I still do not under-
stand its growth requirements and the conditions of culture are such
that very little can be done with it experimentally.

Our own work with S. lunatum has reached the critical stage. We
have a group of marked strains and are attempting to demonstrate re-
combination. Our first experiments have been negative, but since we
are just starting on this phase we are not discouraged.

I am enclosing two reprints on the Spirillum. If you have any
questions on culturing that are not answered in the do not hesitate
to drop me a line.

With best regards.

Sincerely yours,
S. C. Rittenberg

Professor
Department of Bacteriology

SCR: bjw