I'd like to test all possible [ . . . ], single or multiple, and would welcome any contributions. Please don't send
them until after Labor Day. Incidentally, did you get the Ps. fluon. mutants by the penicillin method? Somewhere I picked
up the idea that this bug is very resistant to the drug. For extending our march for intermediates it would be good to use
an organism not closely related to the
Euterobact. we've been working with.
Unless you feel there'd be no point in testing a resistant mutant derived by multiple steps, I'll be glad to try to
make one from one of your stocks when I get back. I must admit the pattern of increasing degrees of specific sulfonamide[?]
resistance (not crossing with PNBA) on successive mutations makes me swallow hard in explaining it as an enzyme of increasingly
altered configuration due [ . . . ] to excessive allelic culturation, for one might expect a single step
also to provide a big distortion in the enzyme resulting in high resistance.
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Yet we know so little about that[?] process that the interpretations I have advanced should hardly be given up on the basis
Congratulations on the indirect selection of Srr, Vr, clones. I simply cannot take Harry's stuff seriously at the present
time, and have been sufficiently convinced of the L and D and N evcombe[?] expts. so that I would have been annoyed at any
conflicting results. But it's good to get further direct evidence, and I'm glad my fears about the small size of the
clones of these rare mutants were not realized.
Sorry I won't be in Minneapolis - am on the ACS program at their Sept. jamboree and think that's enough meeting for
a while. Have a good time. Since the bacteriologists learned last year that they eat at their convention, I trust you'll
use appropriate discretion when the geneticists get together.