ee,

4 November 1947.
Tear Jacques,

Since our last meeting, I have of course come out here to
Madison, which Bsther anc I enjoy very much. I don't have much
of a lab yet, but have been able to get down to work looking
for carbohydrase mutants. K.P.Tink has become interested in the
problem and will set one of his students to the task of synthe-
sizins some of the synthetic glycosides thet will be needed,

\ few carbohydrate mitants have turned up in tne lust two
we-xs that may be of some interest to you. These ere independently
occurring mutations in nitrosen-mustarda treated popul ations:

W-1 (in Y53: T-L-By-ZLac-) Meltose nerative (Mal-)
W-2 tin 58-161: B-M~) . Ghaactose Kee. (Gél-}
Weee (in 58-161} Maltose ner. (aia@al-).

Nore have been found but not ret checked to ensure they are
not pontaminants.

In addition, stocks of 58161 were found to consist of two’
comporients which I label G¥ and ¢® respectively, ani are identified
by typical large and very small colcniew on oertein galaotose-
containing media, SMB asar made up with 1» galactose and 1% "N-Z-
Amine" (4 partial enzymatic hydrolysate of casein supplied by the
Sheffield Company) shows this fairly well. Using peptone or N<-Z-
Tone, which are similar Products, the G® colonies are indistinguish-
able from from G¥. In view of the high proportions of these types
in the 58-161 stocks which had been maintained on 4 peptone-glucose
agar, there most be & rather appreciable rate of mutation. I would
sugrest that this corresponds to your G+/G-. the Gal- referred to
above refers to the ability to prroduce ecid from ralactose.

Attempts to obtaih Sucrose+ variations have not yet succeeded.
If you should happen to pick one up in a biockémical mtant of
Kel2 I would a precilate it. I shall send you the above mentioned
stocks as segn as convenient. Among the other sugyzs, F-le is
positive on: melibiose, sorbitol; slow (and can be pepped up) on
aulcitol; slow on rhamose, and negative on cellobiose, a-methyl
glucoside, and inulin. I forvet to mention that it is + 6n xylose
and arabinose. In addition to sucrose I am trying to obtain +
mutants of the other negative sugags.

Please convey my remembrances and respects to lrs. Iwoff anc
Teissier. Dontt forget to send me your set of rerrints.

Sincerely,

LD fa,