Joemua Lederberg
Madisen, Yisconsin
Jans 4, 1956

or. Joneph Leta
Bvistel Laberatories Ine.
Syracuse, Rew York

Tear Jeet

I was very pleased to hear your extended seeount of parent vork and
to ees how eaoothly everything is going both routine and expleratary. fe I
don't Rave wery much to add right now excess for a few casual seavente.

fepige - I would imagine thie agent would be scest useful act xlcne, in
view of ite lew therapeutic activity, but im combination with renicillin. was it
over triad on that Basis? I also believe thet Cevtslosporin F has a sintlar
agtivity and might be worth looking at. Fimally, do you knew anything of
jyanematin, waich I believe is another penicillin derivative? Ie this last material
commercially available at the present tinet I vould be interested in getting a
enmple of it for triale in comparison with cealeillin for the taduetion of proterlsets
ant would aporeciate any information you may nave adout it,

T was interested toe in the orogreese of your trials with licese. Here
fe another sudstence I an trying to get a handy source of in coansetion with the
same project and have the sane request te make of you. Whet have you been using?

I dida't quite understand what you menzat about the wiacosity effects of
various subatances on the eami-selid agar. le you mean thet the sediwm failed to
gel when theee rarticuler bretas were used? itheat ie your trecise regise ina
making uo the medium with these brothe? From what you said I wondered {f you have
been using » medium of the same ooneiatency that we hava, namely, one which ie
quite sclid dy casun] inepection. I would be willing to bet that the major effeet
of Actinoayeste broths would be prisarily = matter of oH ae it ie « little pacrd
for me te see what elee enn be influencing the rigidity of the ager-gelatin eo rdine-
tion, Your comment om the fantastic toxicity of some broths to fish was interesting
in the light of a previcus suggestion that you leek into your materiel a8 a roseible
replacement for Ratenons io the colacning of lnkes. There may be more of a merket
in this area than you had anticipsted.

Your reactian to ay suggestions about a virue litter were rather
amusing, but I hore you don't give up the idem dompletely. J am aot sure thet it
would take an snsyse to accomplish the desired reeult, and my feelings about this
carticular arvroseh are that it would be beat follewed up on a ourely eapiriecs!
basis once given the imitial fdea. Sines we do have newly available, highly
varified preparations of different viruses, why act?

T would be interested in some sore details on the effect cf icerin on
motility of 2. golf. vid the very high levels of the drug that you had to use
ishibit motility without ishibiting the grewth cf the bacteria? If you are intsrented
in OF?, you can get eancies from the Edgeworth Areenal Station where the Aruy has
been investigating thia tyre of effect. I would euggert you simply write to the
Commanding Officer there.
fe: J. Leia - 2 «= Jana &, 1956

ia our last visit we discussed possible military apclications of sone
of your atrepinie drage. Have you taken this up at all with the Lefenee ievartaentt
{ would urge that you net nsgleet this varticulsr aprroseh curely from petrioeti¢
sotives. I don't know whet interest your company would have ia the matter, but
I would also msypect that the Defence Devartment wewld be interseted is epensoring
further develogment work in that type of area under contract and thie te eemething
alec worth looking inte.

We pax be makiag two tripe this sunner that might interest you, Joe, The
first is a possible exoursion enetvard that might make it peasible for us to visit
you at Syracuse around the and of July or aicdle of August. If that shoeld tura
out, hew would that strike you? What the creciee relevance of the secenc hee for
you, I don't know, Joe, but thers te also 4 baasibility that i will ve traveling to
Tokyo, Jayna the firet week in Geptenbver as a U.S. wapperted delegate to the
Taterastional Genetics Symposium there, If you or Ame] have any comzents to maka on
ne trip of thie kind, I'4 be gind to hear than,

Thanke fer your qomuents on the yeast activity. Hod vright hes been in
touch with Liadegren lately and got what must have been « very sistler recipe and
thie hae been rather ueefal.

in regard to your anti-glucsees, 1t cceurs to me that if you are going to
Randle your teste on a diffusion plate aesay Basia, you wight do fuet as wall to use
& straight-forward indieater like bromereeol purple rather than fesin sethylene dius
ager for the teat. The reason for thie ts that EBS ager is rather trieky in trying
to internret results of uniferely spread plates although it ie the ideal medius
when you are trying to detect ssetors of non-fermenting among fermenting oclonies,
That's all for now,

Se leng,

Jouk
Tine