Robley Williams was one of many virus researchers that Franklin visited during her 1954 trip to the United States. He had
written to her about her recent article on the probable structural configuration of TMV, as revealed by x-ray diffraction
studies, and mused about the differences between her data and those found by he and his colleagues via different methods;
they continued to brainstorm about this in a series of letters. In this letter, she asked Williams to review a new manuscript,
to be sure that she had interpreted his work and that of Gerhard Schramm correctly.
Number of Image Pages:
2 (89,652 Bytes)
1955-11-09 (November 9, 1955)
University of California, Berkeley
Original Repository: Churchill Archives Centre. The Papers of Rosalind Franklin
Reproduced from the Franklin Collection at the Churchill Archives Centre with the permission of the copyright holder.
Many thanks for your letter. As you probably know, I have now received a splendid collection of heavy atom TMV derivatives
from Dr. Fraenkel-Conrat, though not yet the reconstituted virus.
We should be very grateful for criticism and comments on the enclosed manuscript, from you and anybody else interested. As
you will see, it is written rather over-fully in places, because we wanted first to make sure both from you and from Schramm
that we have not misunderstood or unduly distorted the experimental work on which it is based.
When I looked through Schramm's collection of electron micrographs I was very impressed by the consistent appearance of
70 A striations on A-protein rods but not on TMV. Have you observed this at all? Or do you believe that this, too, is due
to impurity, as you state for TMV (in "Advance" Vol. 2). Another thing which has surprised us is Roger Hart's
statement that the short fragments of TMV obtained by ionization do not show a central hole. In Fig. 9 a and b of your 1952
paper the fragments have dark centres. Are these not due to holes?
The central question is, of course, whether the two fragments represented by A-protein monomer and the doughnuts (should we
use this word, or remove it before publication?) are sufficiently uniform in size to justify our speculating about their origin.
Schramm is clearly convinced that they are, and I find his papers
fairly convincing, but I should be interested to know what you think about this.
Do you know whether anybody has studied light-scattering by A-protein monomer? It might just be possible to distinguish,
by this means, between a molecule of the form we suggest and one in which the three X-ray units are side by side. The latter
would be a flat, thin molecule.