Ootober 15, 1947. Dear Ed- If I haven't thanked you yet for sending those extra J Bact reprints, I do so now; I would have run out entirely without the supplementary supply. Everyone here wanted one. . A I met your father last week or so, which as with Peterson too, KY was rather like encountering one's academic gratidparents. The Medical Sehool generally seems to be a less predominant research part of the university than it was at Yele, I suppose because of the r8le of the Ag School. There has still been no opportunity for research work, although my "temporary" office is completed; in a couple of weeks however I should be able to get started. The permanent lab is still being lueprinted and financed, and although slowly is going alang smooth - Supplies and equipment are beginning to come in, some purchased sv ome gift (as biotin from Merok!) We've picked up a good large NY team autoclave as War Surplus for $55, saving over a thousand! ind ° ~ |Not so lucky on a binocular microsoope (Spencer) where we had to ‘ ot yw ~ | pay somewhat over list for immediate delivery. The main immediate e eo” |e is financing an accowitvfrom the Univ. storeroom so that w \ ) I can draw " trivial" supplies and begin to work. ~ N I think I mentioned my progran on glycosidases tn coli. I had ye in mind that there appear to be at least two levels of specificity / in these enzymes (from plat sources): the glycosidic linkage and the nature of the aglucon. Coli "maltase" for example, has no efffect on alpha-methyl glucoside, although both are alpha-glucosides. Some strains of coli, however, do attack &-nethyl glucoside, so that it may be possible tc obtain mutants of the maltose+ K-12 which will 7A also attack the glucoside. Problem: is this modification a change in the "maltose" gene, or in another. It will be necessary to ob- tain a maltose- strain and test for allelism. If a setup can be found whereby a strain mst be "maltose+;X+" to attack X, and either maltose- or X- are inactive, one might infer that both the maltose and the xX gene must be functioning to produce Xase, ergo that two genes are re- quixed for one enzyme. I haven't written this as clearly as I should but perhaps the noiht is down. I realize the possibility of anaphrag- mic mutants, etc., but to cite these too freely is to destroy any chance of verifying the 1:1 theory. On the other hand there mav be somethins fishy about the whole story of glucosidase speoificity, or else about the accepted configu- rations of the disaccharides. Reading the literature, there is a defi- nite correlation between the ability to attack cellobiose (4-glucose © glucoside) and a-methyl glicoside. On the other hand, maltose (4-glucese a glucoside)and b-methy1 glucodide are attacked bi all of the coliforms tested. There is not quite enough to make a definite itdgment, but it should be emphasized that the accepted configurations are based simply on another set of enzymatic sctivities: emilsin. “transformism" is not being abandoned b: any manner of means, but the carbohydrate problem is wne which seemed to fit in well with the help I would be able to get from Biochemistry. Also, Dickson here and one of his students have workéd a method to follow the entire life oy- cle of certain smits in culture. From all I've heard, they should be excellent genetic material, and I'm working now to arrange some sort of collaborative program. Esther is working in Perry Wilson's lab now learning Azotobacter which she may or may not use as material. One of Barker's students (Léve) did his thesis on Azotobacter mutants one of which was blocked in the pyruvate-actbehse reaction! His strain, however, will assimilate only acetate and related compounds, and not pyruvate or more comples sompounds! They obtained several mutants which, in their hands,reverted, and none whioh were clearcut N-nonfixers. You may also be interested in a reference to u bacterial aromati- zation of c~hexanedarboxylic acid: Jezierski & Frei, Helv Physiol Pharm Acta 4:395-400. 1946. E, coli included. As to my thesis: I don't have a suitable draft which could be copied! If Betty is too busy, could you, whenever the Univ. copy is in your hands give it to a professional manuscript copyist and send me the bi11? The storeroom already has my advance payment for binding 3 coples of same (try Demander's, on Elm I fhink). That's about all for now. Best regards.