June 20, 1944.
Dr. Frank H. Johnson
Department of Biology
Princeton University
Princeton, New Jersey
Dear Dr. Johnson:
I am very pleased to learn that you are planning to spend part of the time on your
Guggenheim Fellowship at this Institute. The time from the middle of November to March
is just as satisfactory for this purpose as any time will be before the end of the
war. We shall be able to provide you with some facilities for experimental work, and
you will, of course, also be at liberty to attend lectures in which you are interested
and to take part in seminars. Weekly seminars are held in chemistry and biology, and
also on such special fields as immunochemistry and immunology.
You might well be able to obtain some very interesting results by studying the effects
of hydrostatic pressure on serological reactions. I think that the details of your
experimental program may be discussed after you arrive here. Although we do not yet
have very satisfactory quantitative methods of investigation of artificial antibodies,
it would, I think, be well worth while for you to do some work with Professor Dan.
H. Campbell on the effect of pressure on the conversation of normal globulin into
antibody by interaction with antigen after urea treatment. Some work might also be
done, as you suggest, on the reactions of animal antiserum. In addition, a study might
be made of the effects of increased pressure on the rate of destruction of diphtheria
antitoxin in urea solution—Dr. George G. Wright has been making a quantitative study
of the effects of temperature, urea concentration, and hydrogen ion concentration
on this reaction; the assay method based on neutralization of toxin as shown by a
rabbit skin test, is accurate to perhaps three percent.
I suggest that you bring with you the 15 cc. bomb which you have at hand. Perhaps
it would be worth while to make up another bomb, with capacity about 5 cc., which
need not have windows, in order that pressure could be applied to a small sample of
liquid. If you think that the antitoxin-denaturation problem will interest you, it
might be worth while to make up a battery of simple bombs, since the rate experiments
run for several hours or days.
I have not yet learned from Dr. van Niel whether he will be able to come to Pasadena
during the coming winter or not. I am looking forward to his visit here.
Sincerely yours,
Linus Pauling
