HH S4 Cr

November 28, 1956

Prof. Joshua Lederberg
Department of Genetics
College of Agriculture
University of Wisconsin
Madison 6, Wisconsin

Dear Lederberg:

Iam very happy to find that the detailed structure of the pneumococcal
polysaccharides is now of interest to geneticists as well as organic chemists.
Our recent studies on cross reactions in antipneumococcal and other sera have
led several groups of sugar chemists (including ourselves) to take up these
fascinating polysaccharides once more and your justified complaint about the
loneliness of the Type II substance is being rectified. You will find a partial
solution of the Type Il problem in J. Chem. Soc., 1955, 1537. A full
description of the Type VIII substance, with several surprises, should be out
any minute in the JACS, by J. K. N. Jones and coworker.

I see no reason to doubt Zamenhof's structure for the H. influenzae b
polysaccharide. The pneumococcus VI and XVII substances also contain P and
Dr. Rebers and | 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. Under separate
cover Iam sending you a few reprints on the cross reactions.

With cordial greetings,

Sincerely,

Michael Heidelberger

MH: DP