March 24; 1966

Drt D. H. L. Birshcp
Department of Zoology
University of Edinburgh
Chemical Biology Unit
West Mains Road,
Edinburgh, 9, Scotland

Dear Dr. Bishop:

I will be sending to you soon under separate cover, the two strains,

A19 and Ql3, whicn you require.

       With regard ti3 the questions you raised concerning Qf3,  we are prepar-
ing now our second paper on the properties of Q3 with particular reference to the
RNA and protein.
and G respectively.
from any of the other viruses we have looked at or that have been reported.
lacks tryptophane, and methionine in addition to histidine.

The base compositions are 24.'(, 22.1, 29.5, 23.7 for C, A, U,
Tne amino acid composition of the Qf! is uniquely different
                                             It

As soon DS copies of our paper become available,  I will send them

on to you.

With regard to the question of your coming here, I can say that I

uould be very hapgy indeed to have you do so.
timing, and I would like to hear from you exactly what your preferences are.
Would you prefer to come in the fall or wait until the spring semester?

The only uncertainty is the

       We! are having a bit of a budgetary squeeze because of the Viet Naa
situation here, which has made it somewhat more difficult to provide money for
foreign fellows.  I do think that I will be able to manage it by fall, and I'm
certain that I could handle it for the spring. However, if the latter turns out
to be very inconvenient for you, do let me know. In the meantime, do keep in
touch.

I might note that 3 hope to stop off in Edinburgh on my way to

Naples some time late in April.

Sincerely yours,

S. Spiegelman
Professor of Microbiology

SS : rn