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The Francis Crick Papers

Letter from Sydney Brenner to Francis Crick pdf (642,222 Bytes) transcript of pdf
Letter from Sydney Brenner to Francis Crick
Brenner here reported results from his research with mutations of the phages (bacterial viruses) T2 and T4, research designed to match a mutation in the fine structure of a phage gene to changes in a protein whose synthesis the virus triggered when it infected a bacterial cell. Brenner sought to give experimental support to Crick's sequence hypothesis: that the sequence of the bases in DNA specified the order of the amino acids in the polypeptide chain of proteins.
Item is handwritten.
Number of Image Pages:
2 (642,222 Bytes)
1959-03-24 (March 24, 1959)
Brenner, Sydney
Crick, Francis
Original Repository: Wellcome Library for the History and Understanding of Medicine. Francis Harry Compton Crick Papers
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Reproduced with permission of Sydney Brenner.
Medical Subject Headings (MeSH):
Genetic Code
Exhibit Category:
Deciphering the Genetic Code, 1958-1966
Box Number: 8
Folder Number: PP/CRI/D/1/1/2
Unique Identifier:
Document Type:
Letters (correspondence)
Physical Condition:
Series: Correspondence
SubSeries: Alphabetical Correspondence
SubSubSeries: Correspondence 1
Folder: Correspondence B
March 24 1959
This letter contains very good news. I have now proved, by a rescue experiment, that the o gene controls the head protein. What is more, the same experiment shows that the protein structure can be recombined and segregated and I think this is a very important finding. The experiment was to cross T2o5UV x T4o5 and select for o5. Under these conditions, linkage is destroyed to the following extent: Two markers (h and T) which in a normal cross would be found together in 80 percent of the R, now only show 14 percent coincidence. Five rescued recombinants were picked, selecting for o5 and all had the T4 markers present in original parent i.e. we crossed c plus h2 plus a5 r plus o5 times ch4 plus ar r or and all o5 were ch4tarr. Stocks were grown and fingerprinted. Here are results so far: [diagram] Notice (1) recombinant nature of R stocks showing that differences are not allelic (2) close linkage of peptide B to o5 (3) segregation of peptides A and D in R3.
There will be more data as we apply stains
I will confirm this using isotopes since A and B can be seen in I - D using phenylalanine -- we also have found the homologous chymopeptides [?]. It looks as though my crazy idea is workable -- and I shall push on with it. Genetics going very well and more mutants in o5 cluster. I am going to make a determined search for this part of protein.
Heard from Max about your Harvard job offers: I hope you don't succumb to the temptation. I have been offered one in Wisconsin which has been or will be offered to you as well. Now that the Institute is on the way, I'm not keen to move.
Lets hear all news
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