MEDICAL RESEARCH COUNCIL

NATIONAL INSTITUTE FOR MEDICAL RESEARCH,
THE RIDGEWAY, MILL HILL,
LONDON, N.W.7.

Telegrams: ‘NATINMED, MILL, LONDON.’
Telephone: MILL HILL 3666

 

PRIVY COUNCIL

26th October, 1960.

Professor J. Lederberg,
Dept. of Genetics,
Stanford University,
Stanford,

California.

Dear Josh,

Thank you for your two letters of 3rd and 10th October. I am keeping the
typescript of the periodate paper as you suggest and have only a few camments
(see the end).

The other points.

1. Yes, the symposium on space travel is to be published as a small book by the
Institute of Biology, late this year. If I get any reprints I will send you

one. An examination of some soils from roots of old herbarium plants (Kew
Herbarium) gathered before 1863, shows much highers counts of sporing bacilli than
controls (like the paper, the flowers, etc} and I hope to write this up briefly
somewhere. The “half life" of these soil bacteria seems around 20 years under
such conditions. Identification of them is proving troublesome.

2. This puts a slightly new light on the olan of Paul Ehrlich and myself to
look at the grasshopper glacier, since we would like them to be several centuries
old, and the evidence (such as it is) is that they are very recent. Still, I
will re-draft an estimate, and seek permission fiom the M.R.C. forsich a project.

3. Ihave cited your parer as you suggest, omitting the Nice Conference
volume.

ke Yes, not much more can be done without a male-substance assay, it seems.

5. As to the Mohole project, I will be glad to help if I can. It may prove
very interesting.

6. As far as I know, there were no experiments to show that addition of
periodate after pairing did not reduce the expected recombinant count. That a
number of matings did continue was shown in experiments SN 7,12, 64 but my data
give little clue as to the significance (since the non-periodated controls

Joontecse
were allowed to continue mating; they should be diluted to prevent further
mating). Yet the nuibers of recombinants was in the range of 10-20% of the
controls after allowing for the killing by periodate. This seems too high
to ex»lain the periodate effect, which often gives only 1 of expected
matings. The additional recombinants could plausibly be due to later
matings.

Te Snecific corrections on periodate paper:
p. 1. Will you add the references? (they were omitted from my copy )

Pel, genotypes; W 3064 Vv’ should be Yo ?
w6 delete S
W 3876 Sm’ to be S
W 3776 delete Sm°
W 3770 Sm’ to be S

Table 1. The viable counts are not clear, since the female counts are omitted
(they were from L to R, 98, 120, 148, 120). Also add 'male' and ‘female’ on
appropriate line.

Table 2. is "Untreated male (mixture plated immediately)" sufficiently clear,
or would it be best amplified?

Discussion. Yes, a note on the acrosome would be good,

8, We will be glad to pay for our 150 reprints if you wish: there will
be no difficulty if we get an invoice.

I will not hold this up with other points, but sometime I would like
to know your frank views on the grasshoppers: - is it worth a ereat effort?-
will it be in well with exobiology? Joan joins with me in sending sur
warmest wishes to you and ssther, and to all in the department.

Yours ever,

he