Ostober 10, 1952.

i, George 0. Carrington,
Department of Mioroblology,
Western Reserve University,
Cleveland 6, Ohio.

Dear Mr. Carrington:

In March 1950, I promised to send you our culture W-590 (Luria's
designation 109A) if we ever succeeded in rescuing it again. We are
currently lyophilising our culture sollection, and happened thereby
to run into another vial labelled W-590 from which a viable E. coli
was obtained,

In hopes you might still have some use for it, I am enclosed a
subculture of this strain. It has not been rechecked for ite original
requirements of xanthine or (guanine + uracil), but I truat you may
have retained your interest in it.

The culture is preserved on dry silica gel. It can be resuscitated
by breaking the tube and pouring the gel into broth or onto agar.

Youra sincerely,

Joshua Lederherg
Associate Professor of Genetics.

P.S. Please give Dr, Lampen ay best regards,