sities oan Ye) ae 1 ae) Ce ah | sees ra but 7 Par) pe 2 oP
day to day for so many postscripts that I thought it better to start over.
We had a very pleasant vacation in Canada and Maine, and hope you had an
equally bon voyage. We returned to the lab to find everything in very good
order-- I am especially grateful to you for leaving the Salmonella cultures.
and notes in such trim shape, as it permitted me to resume work without delay.

a

I am waiting for Spicer'dé arrival, expected momentarily, to make more defi- ...
nite plans for the Salmonella work. Before going ahead, it seemed important to-
consult you (last week would have been none too soon). It should not take ae
to clean up the loose ends for e paper on the trammotilization experiments if
we can orranise the work between us. Beyond this, I az hoping to extend the
scope of transduction in Salmonella with diverse phages, and to prepare for a
visit to Chamblee to set up an assembly line there, the logical place to manu-
facture Salmonella types. Spicer will probably emphasize the development of
material and technique for the Salmonella groups, esp. C and E, not hitherto i.
covered, and from some of the literature on phage specificities, it may be feasible J
to bridge these with the 3 and D. Kauffmann has repppted an unusal paratyphi A. we
with XIIz, which may help to bring the A group into the picture i8 necessayy.

The situation that has occupied moat of my attention the last couple of ree
has been the avparent linked traneduction of i--H+ from typhimurium to S¥-543 ( —odgy
but I'll save this to the last.

The stability of 24 Gal+ tranaductions to SW-435 from PLT22/2 has been confirn

The stability of traneinduced genotypes may have nothing to do with the tracks, but.
ce Ca Tee ar Ce Cee ae CMe. ae eT COL mer Pe LY Mahe PK Sela ate bs. Mas
that have not been studied for any other character. (I am sure most of these pointa,
- have come up before, but I don't have any record of our joint speculations). To be

on this point, I have made a Gal- in SW-603 (SW-665) and a Xyl- in SwW-541 ( SW-665)
Both of these mutants are ideal for transduction stulies, giving clear papillee .
with a zero background freqgmacy. SW-665 @ees seem to show. a very efficient. respe
to transduction. A careful co:parison with LA-22 isa in progrese. SW-666 shows a .j%
good many plaques when plated with PLT22 (host range mutants?), but the transdue
is fairly smooth nevertheless. The transinduction to + of both mutants nwkthxrex
te being studied for stability. No linkage of Gal to H+ has been noticed ih trans
lizations of S#-6466.

4 more spontaneous H+ have been picked up from SW-60%, all b. I am inclined to
agree that SW-572 was a fortuitous transinduction. 3ut to avert the question, we
can deal with FA's fron a variety of other serotypes. This has beén done with eM eTes el gt
dublin,san diego, enteritidie, to give in each case a mixture of b and tho FA-type .4
awarma. I am waiting for some additional sera to-check the phasicity (mone- or ai-) @
of the tranainductions. We are both willing to bet they will all be strictly mono- ..
phasic, as is S¥-543. Thie nay ‘be of some use for anticsens for practical serun. 4
proiuction. FA (PLT-22) has also been produced from ene te: VME CGT Ce eee ey
few tested swarms were all b; some fresh platings with the urging of b- antiserum °‘
are in the el A good many new serotypes are already reoresented in these ze
experinents. I think it certainly is time to consider suggestions for replacing the: 4
place nameswith simplified diagnosee--uhleas the artefacts are to be dismissaé as. :
madicon-l, @.... Wilson & Niles (in Topley and Wileon) already supported thie.
I don't have much bearing th¢ the phase of the FA-donor in relation to the pha
of the output. S¥-603 should be a good tests system for this Ce eg
strain, which is almost all phase 1.to start, did give almost all b tranembtild
I have a mimemx plate going now to ewitch its ee rYe\eQe Tm Ast Pears °

 
fr fr] ra z tj urtt s c
ape ane “se 7 ie es 2 FAs mY Wmirnrry

i alba transduced. J hape you can psy somo i
eT a rrr re te Peer ett .
There is no question that the antigen subditution in theae experiments is ee ce
ee eC tk ee! | ¢ranmotilizations. There is a preblem here-
TEP ERC Cm OOM Ma OL ae be invoked. ©.
ere me CMe Cm el as agglutinated flagella, so that only the |
Pee ar er eC MMC eh mt rea should be possible to set up
Pe sre ae a Ce Le ne ee Teer UT Ct ee
ocour in the midst ef ptherH-agglutinated celle. I have not pe CR Cee) ae
the track problem, which is your own very healthy baby, but I do have a small canparis~¥
cw on the influence of b or 1-12 serum on the trahsmotilizations by typhimurium Fa, ¥
This is needed to validate the use of b serum in the {nitial plating when the second
type is muru desired. :
RC MeO Cm Ome ae (with plaquing) by PLT22 on agar, F
I have had rather poor luck in growing PLT22 on typhi H901 or on stanley. Howevey, sam: P.
other phages are turing up that look more promising. .
Re Chi, I have only just grown a batch on Se PCC Oc CLUE) a | %
aot rum many tests. With the original Ohi, both eo ME CMG a UTP en Dla D il
were resistant, F901 and its 1 deriv. are sensitive. I intend to compare a et a ee
donor type trensmotilizations of SW-603, but don't expect that the response depends “4
on the flagellar antigen ae such. Have you done at ms ee
planning? It would certainly be very useful to have any fairty clearcut taxonomic a
criterion for a Salmonella H antigen.
ees eae Ce OM tal) ee the SWo543 situation eccurred os
to me (again?) and ie under way. With the transduction ra eT eats) a ave ts) an
we must reject the notion of their latent retention eS ewe eS)
explain why any FA does not give the full range ef types. f° take typhimurium RA aeth
by way of example, it can be suggested eo Ue oe aren CU es de
Te Sat TUT Th rs ee Oar & as a two factor Bay ete Ua Sere hd x4
Then, H and X would have to be linked, of course, since there co-traneduction ecaurs —
yery much more frequently than with Gal, or as between any markers eo far in Vy t
er eer rte sac Ne Oe X>, as above, the 4 is alse
a one factor traneduction, H- an This would aoe that the H- of SW-543 is a special
inhibitor ef that particular X° (or that this X” is inactive without A abies 2 T
to an incipient geparation of ra eT Ae oP OL Be carne etc. (and
Te eee ese mL A H-. Thie is no stranger than the effect
that the reeidual genotype of typhi or of SW-543 seems to have on the strict monops
auth stability of 4 (if this general interpretation is correct). The ted for this is
the competence of FA from the 1 transinduction itself. If it can trananit either 3
or 4 activity, one has a Pre MT ss Me Cel ee grounds that the perro pe Uae MY]
dual in the first place. The experiment is under way.

We were discussing the use of Fa for ummasking © forms. pa ae ae ot Od
ception fe fatal. In the first place, we can use FA from SW-603, and simply not Fre
transmotilizaténe based on this locus. Secondly, ome can always be susphoious of
ee TR Mads with FA from another type. This 3
seems not so difficult as the prolonged, repeated selections for oti Cat
that may well be unsuccessful. If only as a pretense for collecting additional materir'.3
I think we should keep thia recemmendation. a

For a complete study of O-forms it would, of course, be valuable to have an ae 4
PETC Ce mre teas tlt LT-1 may be a satisfactory &
choice, as it seems to be nicely susceptible to Ohi, and oan be closely tied in with 2
the previous work. I believe we PO eS Ora Te Seren
pose the one mutant we should especially seek would be H+ X° of the above schemes (2
haps we already have X- H® in gallinarua? --This fe another longstanding problem %
get PA from gallinarum pullorum, but on Man sr Oe ae.

ee §deas). a:

oo ae — Pe

4a

ra

 
PFoper ‘seqt vetvampiial cx.
T had onve (a long Oe oe
phase variation, but I ama little « ae

le aay]
Z am not at all happy about the terminology either here or MRA dat ee TT
to “autogento" and"allogenic" seem to be shortsighted, as they simply reflect
how many character bose SE mL Tye mete a CCl eee recipient. It would
be very useful to have a cote SSC LL Sa arte hte for the FA doner and bat T+ GbE Sa
Ct Ee sola nas Te Transduction itself is 4 ses Mrs meee en Cie se)
Cort Th eet act of conveying over, and we would not have te apologize
replacing it with a better now thet we have at least sone idea of what is rs
One The same for FA, Unfortunately, 5
with my feelings about words to the
toe Swe ey Tee Pe th YS ae et

Although the results of the serial transduction experiment (1.¢. Lihat ana)
PRODUCE Lact MOT TTR ae eee b and 1) I am going to resist the temptation to
hold this letter be MC: <a «> ey ag ENO ETS atl Wey mT a inhibit
Los T LT. oe oe ees Pn eo ee Sa system, and this is presumably involved in
the antigen substitution experiments. The inhibition av Ee ode eK although the
ERO eM ey CMTS already presumably equilibrated, but this will have to be
checked. As the typhimrium serum seems also to inhibit the transduction of
SW-603 by altendorr (c,zy2), I doubt if the flagellar component is BUCO COMO
this will have to be CAO oN. Te Mbarara.) pa Ran absorbed sera. At any rate, this has to
be cleaned up before the phenotypes of track-formers ror V)

BUTE Od MT ML NE TEE
be b; ? where Fy have been expected. It.i
Si~543 is misclassified as paratyphi B, and that the second phase wil
wien or some other similar type that I ole oRE ev -t typing eera for.

vot BE) ae tO, s ee eT humming with other work as well. Tom Nelson is CUB
quite buay with kinetic studies on Hfr crosses; not much you don't already know
on Gal-duction. Esther's peculiar unstable coli strains, which shrew ace Est
simul taneously Suscpptible to lambda, Tl, and T2, probably represent garden-vatiety
BR dissociation. (The classification of these phages as pebed ey -1e3 Rg be ee Re eK) 5
seems to have been overlooked, but rok Tl MLS hyv We me mS SRE E Sei te
by most of the wg Eve Lo KT E

I shall be waiting to hear from you soon, but will write myself if anything |
very pertiasnt comes up first,

° Sincerely,

Joshua CS dt bas
P.3. Esther will write AA EP Shae, Srey MeL ST ye yay