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The Joshua Lederberg Papers

Title:
Letter from Herman M. Kalckar to Joshua Lederberg pdf (62,342 Bytes) transcript of pdf
Letter from Herman M. Kalckar to Joshua Lederberg
Description:
Item is handwritten.
Number of Image Pages:
1 (62,342 Bytes)
Date:
1958-10-10 (October 10, 1958)
Creator:
Kalckar, Herman M.
Johns Hopkins University. McCollum-Pratt Institute
Recipient:
Lederberg, Joshua
Rights:
Reproduced with permission of Peter Laursen.
Relation:
Lederberg Grouping: Correspondence C
Box Number: 11
Folder Number: 116
Unique Identifier:
BBAKAZ
Accession Number:
16
Document Type:
Letters (correspondence)
Language:
English
Format:
application/pdf
image/tif
Physical Condition:
Good
Series: Correspondence, 1935-2002
SubSeries: 1953-1960
Folder: Kalckar, Herman & Kurahashi, Kiyoshi
Transcript:
Oct 10 1958
Dear Joshua,
Here are a few questions where I need a little advice. We know now that the static phase in 3096 brought about by Gal-1-P accumulation is a true 'stasis' in the sense that the cells are viable (colony counting after serial dil.). Yet, if these cells are subjected to penicillin (still in the presence of galactose and glycerol) they become nonviable. This happens after 10 hours exposure to penicillin (80 units per ml culture). The turbidity does not fall it stays constant (3096 grown in glycerol (S gal) loses turbidity rapidly in penicillin glycerol). It might of course be of interest for an understanding of the physiology of what I call "gal. induced bacteriostasis" to know for sure that this type of "stasis" does not protect against penicillin. In which way would you recommend us to alter our conditions. More pencillin and shorter exposure? I suppose at least shorter exposure. *)
The lab is still in the long phase of being set up and since hampers of course still the capacity to do experiments.
Sincerely,
Herman
P.S. *) We tried 400 U/ml for 3-4 hrs. Complete killing of the 'static' cells although turb did not fall more than 10-15% at the time of dilution and plats.
Metadata Last Modified Date:
2016-10-06
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