COLORADO

GERALD B.

UNIVERSITY OF COLORADO
MEDICAL CENTER
4200 EAST NINTH AVENUE
DENVER 20, COLORADO

FOUNDATION FOR RESEARCH
IN TUBERCULOSIS

WEBB MEMORIAL BUILDING

November 3, 1955

Dr. Joshua Lederberg
Department of Genetics
University of Wisconsin
Madison 6, Wisconsin

Dear Joshua:

As you can imagine, I am delighted that Larry has decided to join
us. Dr. Waring is still away and hasn't heard the good news, but I am
sure he shares my enthusiasme

The "proposal for a proposal" has been polished up and is in the
process of being typed for distribution. Perhaps it will be done soon
enough to be enclosed in this letter. I appreciate your help in prepar
ing ite

Do try to make the St. Louis meeting. As I told you, I think
we would all benefit from your unbiased approach to some of our pet pro-
blems.e

I nave heard, unofficially, that the grant request which we sent
to the American Trudeau Society on the subject of the metabolism of ison-
jazid has been approvede Two of our people are working on techniques
and are about ready to start working on animal and human sera.

I enjoyed your remarks in the letter to the editor. There is much
too little dissemination of this kind of information amongst the profession,
to sav noting of the public.

I have been laboring through Harris's book. I have scanned it
completely once, but I am now reading it more thoroughly. I will have
to admit there is a very great deal of new information on medical genetics
that I had no inkling of vrior to your arousing my interest in it.

I have corresponded with Herndon at Bowman Gray and Neel at Michigan
to add to our file of information on Departments of Genetics in iedical
Schools, They were not able to add anything illuminating, but their inter-
est and enthusiasm in the subject should bear some weight.

I have just been reading Jensen's article, "Some Remarks Concerm-
ing Attenuated Isoniazid-Resistant Strains of Tubercle Bacilli," in the
January, 1955, issue of Acta. Path. Micr. Scand. Jensen obviously is
not aware of Gardner's work on the catalase activity of various strains
Dr. Joshue Lederberg ~2= November 3, 1955

of mycobacteria. As you will remember, the sensitive wild strains were
catalase positive. There were various types of isoniazid resistant mutants
ranging from slightly reduced catalase activity to complete absence there-
of. There appears to be a good correlation between catalase activity

of these isoniazid resistant mutants and the!"pathogene& jy not only for
experimental animals including the guinea pig, but also man. In other
words, there are plenty of isoniazid resistant mutants capable of milti-
plying in guinea pigs at the normal rate, namely those that are catalase
positive. Jensen, also, does not seem to be aware that the BCG organism
is catalase positive, and interestingly enough can be made isoniazid
resistant, and as I understand it, with comparable reduction in catalase
activity. Unfortunately I have not checked the above with Gardner, since
he is out of town at the moment.

With my very best to you and Esther, I am

Sincerely,

aE ose

RSM: wm