7 September 1955
Dr. A . Rich
Cavendish Laboratory
Free School Lane
Cambridge
England
Dear Alex:
I was interested to receive your letter of 28 August, especially since the 27 August
issue of NATURE has not yet arrived in Pasadena.
Your proposed structure for trigonal polyglycine (polyglycine II) looks good to me.
When your letter arrived I thought that it referred to a structure that I had constructed
once, but on checking over my models I find that such a model is not at hand, and
I think that probably my memory confused it with structure 17 described by Corey and
me in our paper in Proc. Nat. Acad. Sci. U.S., 37, 729 (1951). This is a tetragonal
structure with a = 4.8 A and c = 10.4 A, composed of helixes with four residues per
turn. We said in the publication that the structure is "not suited to formation of
intramolecular or intermolecular hydrogen bonds (except possibly for polyglycine only,
in a tetragonal framework with a = 4.8 A)." The calculated density is 1.58, approximately
the same as for your structure.
I am glad to hear that your RNA work is going along well, and also that you have been
seeing Peter and Linda.
With best regards, I am
Sincerely yours,
Linus Pauling:W
Cc: Dr. Crick
Prof. Corey
