November 28, 1956

Prof. Joshua Laderberg
Department of Genetics
College of Agriculture
Univer 5 ity of W isc on~in
Madison 6, W tscons in

Dear Laderberg:

    I am very happy to find that the detailed structure of the pneumococcal
polyaacchrvidcs is now of intertot to geneticists as well PB organic chemists.
Our recent studies on erose raractiono tn antipnaumococcal and other sera hrvc
led several groups of mgar chamiata (including our1~elves) to take up these
fascinating polyoacchartdss once more and your justified complaint about the
loneliness of the Type ullt substance is being rectified.  You will find 85 partial
solution of the Type Utprobhrn in J. Cham. Sac., 1955, 1537. A full
description of the Type VIII substance, with several surprises, should be out
any minute in the JAGS, by J. K, N. Jones and coworker.

I see no reason to doubt Zamenhof'rs structure for the €3, Mluensas b

polysaccharide.  The pneumococcus VI and XVXU substances also contain P and
Dr. Reabers and I are working on their structure now.

Thank you very much for the reprints,  I greatly admire the way you

have all sorts of complicated factors under strict control.
cover I am sanding you a few reprints on the cross reactions.

Under separate

With cordial greetings,

Sincerely,

Michael Weidelbcrger

RBM:DP