Shecmnye

September 13, 1956

Dear George:

I would like to help you as mich as reasonably possible, but hope you
can be patient in waiting for it. Among the 50 &odd presumptive fertile
strains that we had collected, only the three enclosed (plus K-12 and
"OG" = N@TC 122) are recorded as being lysed by 72. I suspect that the
* T phages are "“rough-specific", i.e., that rough variants will have to
isolated from other strains to find susceptébles.

During the next few months, we will be handling several hundred fur ther
cultures, eapscially the various serological Type cultures of E. coli. I
will plan to keep duplicates as we transfer them, ani will forward these
to you as they accumulate, for you to test or whatewr you please. I wuld
prefer that we did not take the responsibility for screening them against
T2, as we will have our hands full anyhow, and they should be looked at
intensively (¢e.g., various T2 and mtant stocks) for your purposes. You might
find that some of the "naturally" T2-resistant stocks are already mitable
for the seglection of 1T2 mitants, so even these may be of some use to you.

This is a good idea. Good luck.

Sincerely,

Josma Jederberg

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