October 16, 1952

Dear Dr. Ray:

I am glad my letter finally did catch up with you. The reprint was
sent fram Seattle.

Just the other day, Dr. Haper mentioned that you might be hoining
him here for your fellowship. I shall be looking forward to seeing you
on campus for closer disouesions.

Salmonella typhinuriua ie a primary parasite of rodents, but Le
also the most frequent agent of Salnonella food pokeonings. It 1e net
regarded as a serious pathogen for man, but ordinary precautions against
accidental ingestion should be taken-- such things aa plugging pipettes,
autoclaving discarded cultures and, above all, washing your hands. I hope
this does not sound too imposing, though it might require on undesirable
shange of routine. If you would like the cultures now, I will be happy to
send them inmediately. As you will be coming to Wisconsin yourself, how-
ever, perhaps you would prefer to wait until you get here and we can die
cuss the possibilities more glosely. By then, we may have some E. coli
material that would be nearly, but not quite, comparable to the Salmonella.

Salmonella ie likely to grow on the same routine media you are alroady
using. Ite nutritional behavior ie essentially identical with that of E. coli;
that is, in contrast te Pseudomonas, it hee a mixed aerobic and glycolytic
utilization of eugars, with no special growth factor requirements.

Are ingested bacteria completely destroyed? Ie there any chance of
bacteria sutviving in the protected enviroment of an amebie cyst? This ia
a question rather parallel to the survival of phage in spotes of lysogenic
bacteria,

If you will anewer affirmatively, I'11 eend the Salmonellae by return
mail. They will include, ag labelled, a non-flagellated, a paralysed and a
motile culture. The motility of the cultures should be checked from time to
time, Brow broth, but their genetic stability 4a quite goed and should
withstand enything but the most drastic selection for motility.

Sincerely,

: Jo shua Lederberg