February 12, 1955

Dr. H. Lichstein
Department of Bacteriology
University of Minnesota
Minneapolis, Minn.

Dear Herman:

Pardon me for running off so suddenly at the airport to catch the
earlier plane. It was not only a matter of tims, but a precaution against
the Madison field closing down, which might have happened later. It turned
out that the front had not yet reached Madison, and the flight although
terribly bumpy was not delayed.

I had a very good éffiie during my visit, am sorry it had to be so hur-
ried. We may try to drive up during the spring for a more leisurely visit.

You probably remember our discussion of the anaerogenic mitants of
E. coli selected by resistance to chloroacetate. I am enclosing a new one,
selected on nutrient agar + chloroacetamide, 2 mg/ml (sic). Apparently
one can get away with autoclaving the amide (10% aq.) for later supplemsnta-
tion; I am not so sure about the acid, even if neutralized. This mtant is
recorded as W-2754. It waa obtained from K-12 (lambda-sensitive) and should
be strictly comparable with it except for the " Cla™ " matation.

The literature on this bug is rabher confusing; the only important papers
(unless there is some later work I have not been able to find) are these
three:

1. Penfold, W.J. 1913 Jour. Hyg. 13:35

2. Harden,A. and Penfold, %.J. Proc. Roy. Soc. Lond., B85: 415
3. Grey, F.G. 1914 ib. 87: 461, 472

(4. 1924 ib. 96:156 and others listed at 103:320).

The firat¥two give the Cla™ as anaerogenic on glucose (let me call this ag~);
but agt on mannitol, etc., and formate. I have had no trouble confirming this,
and W-2754 agrees. Grey mentions another type as formate ag-, but he got
this from a different strain; Penfold also mentions a formate ag- obtained

with ethglene chlorhydrin, I have not been able to confirm this, but will keep
a lookout for it.

Greg's later papers are not very useful, but he does point out 1) that
the block may relate to rH, since mannitol behaves differently ‘one should test
whether pyruvate is itself dissaimllated in the presence of mannitol], and 2),
an odd result that warrants confirmation, that citrate, amdéng others, can be
"fermented" by coli in the presence of formate.
Looking over gy old notes and these papers (I had overlooked Grey before),
I feel a great temptation to delve into the chem&a&try of this odd mtant, but
as I told you I had beéter stick to my knitting. If you can turn up something
really interesting withtit, I should clean up the genetic loose ends lindirect
selection} mapping]. I did not do mech myself beyond what was described earlier,
though I played aoa rather fruitlesslp with acetate as a differential carbon
source, and I have one experiment in which gas production from pyruvate was tested,
and found deficient in the mtant.

There is one thing I should finish up, a differential medium to isolate formate-
negative mutants, and try to confirm that part of the olf story.

It may help if I recapitilate the gross fermentation properties of the mutant:

Cla® (wild type) Cla”
A G A G
glucose + + + -
mannitol + + + +
formate + +
(pyruvate } + -

I have not yet rechecked the nutrition of W~2754. It ought to be a prototroph.

Yours sincerely,

4 at
4 Fe

pana Leaernsig

P.S? I found the enclosed red tag in my coat phcket: tt probably belongs to
the Union coat rack.

JL