UNIVERSITY OF ILLINOIS
DEPARTMENT OF ENTOMOLOGY November 9,1950
303 HARKER HALL
URBANA, ILLINOIS
U.S.A.

Dear Dr. Lederberg,

We Yave been working here for soma time on the isolation of a new b-vitamin,
provisionally named Brywhich is required by thek mealworm.We would like to know
whether this factor plays any role én bacterial metabolism and would like to
test its effect on mutants which require unidentified B-factors.If you should heve
any strains with unknown requirements we would be happy ,to test for the effect
of Ba here,or if you prefer,send you some of our concentrates,

yours

Very sincerel
TL Frankl

*rofessor o Lntomology