MERCK & CO,ING.

RAHWAY, N. J.

RESEARCH & DEVELOPMENT DIVISION October 7, 1947

Dr. Joshua Lederberg

Assistant Professor of Genetics
College of Agriculture

The University of Wisconsin
Madison 6, Wisconsin

Dear Dr. Lederberg:
In response to your letter of September 29, we are
happy to send to you, under separate cover, without charge,

the following samples for use in your new laboratory for re-
search in the genetics of microorganisms:

Our Research

Amount Material Number
i 4.6 mg. dl-Desthioallobiotin .....e.. 5R2462
-_ 100 mg. Biotin e@enveceeveeeevetp ev aeeneneee -

100 mg. 4-Methyl-5-8-hydroxyethyl
thiazole ...cccsecsesevcces ~
~ 100 mg. 2=-Methyl-5-bromonsthyl-6-amino-
pyrimidine dihydrobromide

technical ...cwcccccesvvves 6R2515
v 1 gm. 1-Pantoyl lactone ........06. 7R2176
“100 mg. Pyridoxal hydrochloride ..... 5R586
~ 100 mg. Pyridoxamine (base) .......0. 6R9520

We are sorry that we have only a small quantity of
dl-desthioallobiotin and therefore cannot send the 1 gram which
you request. We do not have any of the pantoate or citrulline
and do not know where they can be obtained.

Thank you for sending the reprint on EB. coli. We
shall be on the lookout for it.

Yours very truly,

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Director, Mitrobiological Research
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