December 18, 1951

Dr, G. Bertahi

Department of Bacterlology
University of DLlinois
Urbana, Dlincits

Dear Joe;

Thank you for so promptly replying to my letter and discussing
Bord's work. I am, of course, mors interested in the possibility
that lyasis-inhibition 1s a feature of Boyd's experiments, than the
lass likely notion that Boyd's suggestion of heterogeneity will
explain T2r*,

I am not clear as to your conceptual objection to this notion
but hops that we can get together and talk about it. I did not mean
to suggest that the lysogenic equilibrium is itself one of lysis-
inhibitdon, but rather that this 1s the first stem in keeping intact
bacteria and phage growing together long enough for lysogenicity
to develop. But anyhow, Esther has been working on this aspect for
some time (since before Boyd's paper). She dcas not confirm Boyd's
result in detail, for the K-12 system. But the picture is very com-
plicated, and will have to ba straightened out by singis cell studies,
which we are preparing to do.

Could you pass a megsage to Lu? I ran across a paper by Yang and
White (J. Path. Bact., 36: 187-200, 1934.) In an appendix by white, there
is a discussion of experiments on the mechanism of resistance to phage
in V. cholerae. He notes tha variability of numbers of resistants from
culture to culture, and comments that this is evidence of mutational
origin, He also set up some selection experiments of more or less indirect
sorts, and succeeded in obtaining resistants by treatment sithervwith
antiserum+complement or with agglutinating saline. It is a rather crude
anticipation, but may be of some historicak interest in connection with
Luria and Delbruck, 1943 (Genetics).

Sincerely,

Joshua Lederberg