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The Sol Spiegelman Papers

Letter from Sol Spiegelman to Martin R. Pollock pdf (95,921 Bytes) transcript of pdf
Letter from Sol Spiegelman to Martin R. Pollock
Number of Image Pages:
1 (95,921 Bytes)
1951-10-19 (October 19, 1951)
Spiegelman, Sol
Pollock, Martin R.
Medical Research Council. National Institute for Medical Research
This item is in the public domain. It may be used without permission.
Medical Subject Headings (MeSH):
Exhibit Category:
RNA-DNA Hybridization in Viruses, 1955-1965
Box Number: 9
Folder Number: 29
Unique Identifier:
Document Type:
Letters (correspondence)
Physical Condition:
Series: Correspondence, 1946-1983
Folder: Pollock, Martin, 1946-1966
October 19, 1951
Dear Pollock:
Thank you very much for your letter of October 16. The results on the penicillin system are as surprising as they are exciting. One would not have guessed a priori that such a small number of molecules would be adequate for maximal adaptation. I wonder whether you already have available the information which would tell us how many molecules can actually be fixed by an inadapted cell. This information might enable one to make some estimation of the number of active sites. It is possible that you dealing with a situation in which the enzyme-forming system preexists and what you are following is essentially enzyme formation. It is undoubtedly fortuitous that the number 100 is of the same order of magnitude as our estimation of the number of discrete enzyme-forming elements.
In answer to the question which you raise, I am afraid that I don't have any scheme for visualizing how our particles function in promoting enzyme synthesis. We have recently been able to demonstrate fairly conclusively with the maltose system that no complex protein precursor exists which can be converted into active enzyme without the participation of the free amino acid pool of the cell. While our results cannot eliminate the involvement of a complex precursor, they do make it necessary to postulate primary peptide bond formation as a necessary stage. They suggest that complex precursors are broken down to their constituent amino acids and enzyme formation proceeds from scratch at this level. As you can well imagine, theis result was something of a surprise to us and makes it even less likely that we will be in a position in the immediate future of visualizing a mechanism for enzyme synthesis.
At the present itme, I am planning to attend the Congress in Paris next year. Unless unforeseen difficultites arise between now and next summer, I anticipate getting together with you for an extended discussion.
Sincerely yours,
S. Spiegelman
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