October 20, 1952
Dear Korton:
Last rec'd: yours of the lith ete.
The Sii- cultures you asked for are in the mail, as follows:

&) lyophil tubes, when there remains at least one more in apparently good
condition. Some of these had incipient cracks, but were intact and should
domif opened proaptiy.

by vial-elants, when this subculture required the opening of the ultimate tube.

c) the following for your interest:

SW-£63:  GW~543 + FA(S%~553: dublin-c} gp transduction

sWebd4 2 " * gas dlego eh or enx transduction

BRROO5 3 Ayl~ irpai Sw-541. The 471 rauctions of tne transductions to +
from FA(Su-544) ox FA(LT-2) are very baffling, pussibly an anomalou
temperature respouse. The strain is self-lytie (occ. plaques) on
Eald-xy lose.

S#-175 and GW-a48 are recorded ag having not baen saved. SW-~176 (not -177 as
previously recorded} was Lost.

Yuaer notes: 1 aa puttiag “idvards! culiures down ag 3v-701 -90, 701 corresponding
te his wi (Ky. ag. Ep. Bull. 40), and so ca. Si-703 way be aku self-lytic.

vn the otaai lai, & aoo-byi2 coonene is present, plieked up in routine checks
of antdatrau-agar, and datar in direct streaking anid picking. I don't know yet
wuether this ie a recent cugtuckuwit or an anclent sutaat.

Zt in Yeussuriag ww dear Wiad plage oway have soe UNe > after ailf

Ccuraraing dislureusces oetiee.a geaducidon und Salmoneile transduction, I had
thougn’ we aad hed all kaamghisawiic that out, but perheps this was with Bruce.
Gf suurse, any ci a onmbsr of things are possible, and fave to be tried, Fe
certainly should not generalize from the possibly uniaue behavior of individual
phages, isdividually grown. This is essentially tre urnveriying prdnciple of

ay further loterest bere, ani I think you are very wise, om the other herd,

to cpmsclidate cur sketchy intormation by en inta:sive study of the system at
hand,

Ag to facte ani hypotheses re S#~543: hypothesis first! The results on non~
limkage in the progeny test pointed to just the picture you queried in your
letter, that SiW-543 carries a specific b aileie #hich is dependent on B+ (or

to say the same thing, suppressed by B-}. In this connection it waa interesting
tp test the spontaneous motile reversions to b, whether thay were distinct allele
A’1, or B+, The facts are rather more confusing. My first scorings of the trans-
ductions of SW-543 were based on the selective action of i~serum, and all the
transducess were immobilised, while various controls showed that the serua
passed b phases. In subsequent teste, however, b phases have appeared fairly
frequently (about 1/3) in the progeny tests, so that this evidence does, after
all, support the linkage hypothesis. This would make the story rather parallel
to the auto- and allo-genic transformations in pasumococcus (hoprible terminology !--
In desperation, I would prefer to see “hologenic" and"oligogenic", which is almpst
as bad.) I can't say yet whether the discrepancies betweem immobilization and
slide-agglutination are trivial or important. They may reflect an unsuspected
complexity of the b antigen, and require a thorough antigenic analysis. There has
been some hint of this in transductions from abony (b-enx) to para B. The b transin-
ductions are of two kinds, one typical b. The other gives buds 4nd swarms in

b serum agar, but the outcome still agglutinates, less strongly, in b reagents.

The transductions of several othervtypes to SW-543 have been checked, in each case
the FA type is recovered as well as h. Spme of them have been sent. They include:
am, gp, eh(enx?), r, and possibly co, as well as, of course, 1 and 1.2. Some others
are in the works, specially second~phases.

The SW-543 story has now to be gone over very carefully, with all of the derived
stocks presently at hand, and thoroughly checked. Until this is done, I would not
want to be committed to any definite conclusions. I intend to do 1 ppogeny test
with one of the other transdidactions, probably/ r, as well as i.

the Berry-McUarthy—Plough story sounds as phony 23 the aiternative-requirement
matante . TORQ MOM OLE XR LX EE MNAMER AK I hope Bernie can be
persuaded to chack the gexaixotrooh recombinants.

feendue § Tranaduction cartainly dioss nob prove a chromosomal prophage, but itd does
speak for 2 hitherto unexractedly close relationship of the phace with the genetis
material of the host cell. 7m

Good Luck on your sloction cameaign.

Sinesrely,

Jognua Lederberg