HUMANISM AND PEACE
To: Prof. Pauling
From: Walt
Subject: Possibility of Fractionating Wool
In the discussion the other day you referred to papers by Goddard. The exact references
are D. R. Goddard & L. Michaelis, J. Biol. Chem. 106, 605 (1934) and 112, 361 (1935).
I would like to summarize the salient points of these papers.
In the first paper, the authors describe the reduction of the –S–S– bonds in wool
by such agents as thioglycolic acid, potassium cyanide, or sodium sulfide. The solubility
and enzyme digestibility of the sulfhydryl protein reproduced differ greatly from
these properties of the original wool. The sulfhydryl protein is easily acidized
by air or mild oxidizing agents to a product which, in contrast to wool, is amorphous,
soluble in alkali, and digestible by pepsin or trypsin.
In the second paper, the preparation of derivatives of reduced keratin (kerateine)
is described. These derivatives were formed by reacting the –S–H with iodoacetic
acid. Only carboxymethylkerateine (the derivative from iodoacetic acid) is sufficiently
soluble to permit an attempt of fractionation which in this case was achieved by the
use of ammonium sulfate. From 50g. of starting material, 30 g. of fraction A (the
less soluble) and 2g. of fraction B (the more soluble) were obtained. The S, N, and
amino N content of fraction A is much like that of the original protein but fraction
B has higher S and lower n and amino N content. They differ in solubility and isoelectric
behavior.
It is certainly interesting to note that the quantified fraction A and B which were
isolated and in the proportions which one might expect if that is one C-chain per
2 AB6-calles and also that fraction A to is less soluble than fraction B.
I have checked Chemical Abstracts for the last fifteen years under the headings of
“Hair,” “Keratin,” and “Wool” but I have not been able to find any papers of interest.
The most feasible method of fractionating wool seems, therefore, to be the fractionation
of the carboxymethyl derivative of the reduced protein.
Walt.
