May 27, 1952
Dear Ed:

I have your note of the 26th, and wish I could help you on your remest.
Honever, as you know, our mitation factory is devoted to stocks far genetic
analysis, which means that very few of our mtants are uncompiicated single
auxotrophs—— almost all of them are tied yp with several other markers in
the same strain. About the only really stablessingle auxotroph I have is the
methionineless 58-161 of K~12, which I imagine you, or some of your colleagues
at Chicago, must have already. As you would already know, such biochemical
enthusiasts as Davis, Adelberg, Gots, Umbargar etc., probably have concentrated
their efforts in a more useful direction for you. But I would, after all,
suggest that you would be best off collecting your mtants yourself-~ you would
have acccherent collection, and know a good deal more of the idiosgncrasiges
and pedigree-obscurities than would otherwise be possible.

Yours,

Joshua Lederberg