Skip to main contentU.S. National Library of MedicineU.S. National Library of Medicine

Profiles in Science
Pinterest badge Follow Profiles in Science on Pinterest!

The Joshua Lederberg Papers

Letter from Joshua Lederberg to Max Zelle pdf (62,996 Bytes) transcript of pdf
Letter from Joshua Lederberg to Max Zelle
Number of Image Pages:
1 (62,996 Bytes)
1949-07-29 (July 29, 1949)
Lederberg, Joshua
Zelle, Max
This item is in the public domain. It may be used without permission.
Lederberg Grouping: Correspondence B
Box Number: 8
Folder Number: 139
Unique Identifier:
Accession Number:
Document Type:
Letters (correspondence)
Physical Condition:
Series: Correspondence, 1935-2002
SubSeries: 1947-1953
Folder: Zelle, Max
July 29, 1949.
Dear Max:
H-168, Lacv.Xylv.Mtlv. etc., has been recovered from the cultures you lately sent, and by now you must have received a copy which has been mailed to you. We tried to reproduce the loss of Xyl+, but in several hundred tests, every Mtlv has been Xylv. The presumption of a second crossing seems to be most likely, but unprovable. I wonder how much of the work on H168 depended on the persistence of the Xyl-? As I have lately been trying to think about it, your single-cell work was directed as answering several questions: a) that single cells so segregate, certainly proven beyond doubt. B) whether the aberrant ratios could be explained by lethals -- very likely, but not directly provable because (probably) of multinucleous cells. C) whether there are two or four strands, and whether segregation occurs in one or two divisions -- the answer to this is a little uncertain, because the previous heterozygotes had one type of segregant so predominant. H-206 should be a superior stock for answering this question, because the 3 classes which do occur are so nearly equal in frequency. I can't yet answer your question about H-206; if you are having trouble reisolating it, let me know and I'll send you another stock. I don't know what else it is heterozygous for.
If you've gotten back to work, let's discuss what's next.
Metadata Last Modified Date:
Linked Data:
RDF/XML     JSON     JSON-LD     N3/Turtle     N-Triples