December 18, 1951

Dr, Jean Dufrency
U. Calif., College of Phanmaay
San Francisco 22, California

Dear Dr. Dufrenoy:

Your paper with Dr. Pratt on cepharantine (J. Bact. 59:310-312)
was recalled to my attention recently. The morphogenetic effect on
E, coli is of some interest, because we have encountered the vesi-
cular forms in a pleomorphic E. coli which we are studying for
the possible genetic implications.

I realize that you quote a commercial source in Japan, but I
wonder if I can still ask the favor of a small sample (10-20 mg) for
som preliminary experiments. If you can give me any further infor-
mation that would facilitate securing thie alkaloid through commercial
channels, I would appreciate this toc.

Has this study been continued beyond the cited ncete?
Yours sincerely,

Joshua Lederberg
Associate Fre2zessor of Genetica

P.S. Have youbtried staining the vesicles with tetrazolium? The vesicles
of our strain givs a very interesting picture’

“

dp *