June 18, 1954 Dr. P. R. Edwards Communicable Disease Center Box 185 Chamblee, Georgia Dear Phil: I hope your airconditioning system is working this summers at least if our weather haa anything to do with yours! Ag you know, I haven't been doing very much with Salmonella during the last year, except for some micromanipulation work. Do you remember those "“traiis" into soft agar that you often get with, 6.g., TM2 —x various non-motiles? Anyhow, Sruce ani I had figured that these maunt ceils which had veceived an abortive fragment which conferred motility but did not reproduce along -iith the cells. ‘is have euch been able to confirm this by direct mlcroscopic experiments, motile celis having been picked early out of mixtures of 0 forms and phage. These give rise tu progeny which are motile, but consis— tently divide to give ohe motile, one non-motile daughter for aany gous cations (up to 60 in one exceriment). The interesting thing is that tne initial trans- ducing phage particle carries not ona fragment, put a darge oundis of thom that are sortal out during the first 5 or 10 divisions, so that the initial motile celi gives a famiiy of anywhere from 5 to 100 motiles before these than settla down to the one motile/ona-non-mtile just deseribed. There is an interesting genetic problem just what these "fragments" are— I think probably not genes after all (in this case) but non-reproducing gem products. But most of my time lately (between trips and hot spells) has been spent on Looking for the sexual ats in E, coli K-12, and not long ago I had my first «ncouragement. The trick is to use om motile, one non—notile strain for the parents. With the “high frequency of recombination" strains one can then f'imi a fair number of curious pairs, tumbling around each other, and joined Laterally (by a so-far inkkwible connection). These separate after and hour or two, enc the “exconjugants" then show a very high incidence of recombination, about 50~60%, so this is clearly hg sexual pairing. Probably a nucleus is passed from one ecwll to the other; there are severai nuclei in each ceil, vs this does not destroy either of them, The morphology atiil has to be worked out. But back to Salmonella. In addition to the reprints from Iseki, I have been in touch with another Japanese (Uetake) who cialms similar gssults, the transformafion of Fy to Ey (or more often to a 3,10,15 type) by phage, and Aleck Bernstein here would like to confirm the results. In previous requests for strains, I had emphasized groups B ami D, and we have very few group © strains. I attach a list with my request for your assistance, Have you bsen engagdd in any of this at all? Aleck also has done a few transductions with S, wien and 5. dar—es~salaamdé to try and clear up the genetics of the lw factor, Since the tranmsducticns so far have only gone one way, the results are not so certain, but it looks (as one might expect) as if Jw in S. dar-es-salaam is a phase~] homolog; lw in wien is less cer- ~2~ PR. Rdwards 6/18/54 tain: it probably is phase 2, but still might be an aberrant (duplicated) phase 1 like N97 java. Anyhow, if I may, I am sending a few strains under separate cover (as described on enclosure) for serological confirmation. I am sure to have missed Pittsburgh ani a change to talk things over with youe Aleck has a rather confusing story on the Afd fertility of the specific coli- forms, ami wo uay be begging some more strains of EB, coli 055 and OllL Lf you have been handling any more outbreaks. Has anything else come in of intepest-- any 0 forms, for eximple? I know how overwhelmed you are with the routine work, but I am always looking forward to ancther review, for example, of tne types that cume in. Une polnt in this connecticn does trouble me. As I understand it, the State of wisconsin (and cthers} males 4 degal distinction between typhi, puraB as against other types like typhimuriug. In view of the increasing confusion of bacteriological types in different clinical pictures (cf. your Ky Bull 525, p.34, second paragraph, last sentences) shoulcn't these matters be reviewad? At any rate, I wonder if you could heip se find eny compilaticn of the current practices of the different states insofar as different serotypes are dignified with different legal restrictions (in certificates for foud nandlers ete.) auother gusstion came up lu a convorsaticn with Lupos (on the TAB vaccine experiments). Wa were both surptised to learn of the failure of prophylactic vac- Cinabion for pullorumgull inarwa. Ti this is right, it snouvld be rather disturbing for tm TAB problen, shoulda't it? Or is there some special angie on the bird infec- tens. sanyacw, Dubos would Like to Know ig thera is any animai Satmonellosia (espocially if ina convenient oxperimental animal) were one san demonstrate protective prophylac- tic iniauniy againsi the “natural" dissase. BXER Yicase give best regards io your associates and assistants from Esther and myseii. any chance at all of ever seeing you in these parts? wae whe Ss Josivua Lederber g