MINISTERIO DE AGRICULTURA Y GANADERIA DE LA NACION

DIRECCION GENERAL DE INVESTIGACIONES AGRICOLAS
INSTITUTO DE FITOTECNIA

DIRECCION POSTAL:
INSTITUTO DE FITOTECNIA

DIRECTOR

ING. AGR. JOSE VALLEGA

CASTELAR
REPUBLICA ARGENTINA

Castelar, November 23, 1953.

Dred eLederberg tbc I fF
Departemnt of Genetics '
University of Wisconsin

Madison 6, Wisconsin.

Ussedc

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Dear Dr.lederberg: my

As I an Working with some mutants of Baci#lus
subtilis with a nitrate and nitrite reduction process different
from the normal pattern of this microorganism, I am interested
to repeat the experiencies with Escherischia coli, better known
from a genetical viewpoint. As consecuence, I am asking you for,
if possible, the mutants of the K-12 strain which you consider
the best for studying that problem.

Unfortunavely, these mutants can not be obtained in my country,
as far as I know and I am obliged to disturb you.e

Any comment or suggestion abouk this theme, will be well accenvte.
Thanking you your kindness, I remain,

Yours very truly

Cem tel Ce, Font

Ce

Swald AeFavret
Instituto de Fitotecnia
Castelar.

Argentinae

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