DEPARTMENT OF GENETICS
FACULTY OF MEDICINE, OSAKA UNIVERSITY

Joancho- 33, Kitaku, Osaka, Japan,

Sert, lo, 1951

Dr. I. Orskov

International Salmonelia Centre,
Statens Seruminstitute,
Copenhagen.

Dear Dr. Orskov

I am currently working on genetic repression of mating
activity of male bacteria cf K-12 by a factor so called
drug resistance factor.

The mating capacity is supressed if the factor is
introduced into a male bacteria. 1 would like to test
possibilities whether the repression is caused by change
of surface substance of the male bacteria or resultethe
other changes of male activity such as inability to form
mating bridge.

Since your anti-F serum shows very specific on ale
substance, the agent seems very valuable and eftective for
the experiment.

I am grateful if you pew coul. Gere 2€ Sone Ll ye ,
anti-F serum, and if you couidteis me tne critica conaition
to make slide agglutination test. is it same as usual
slide aggututination test:

I have sent some péprints of my work to you by separate
cover. a

Sincerely yours,

bobtnent Aireta—

Jakinori Hirota