"On degenerate templates and the adaptor hypothesis"

Date:: 1955

Reference:: PP/CRI/H/1/38

Catalogue details

Licence: In copyright

Credit: "On degenerate templates and the adaptor hypothesis". Source: Wellcome Collection.

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then Gamow's a, which in his notation is ■0= i A V A 'V 2 A or more conveniently written CAA, CBA,. BAD or BBD In his code 12 of his' amino acids have Í+ possible representations and the remaining 8 have 2 représentât ions, making a total of - 6U representations in all, this being the number of possible permutations of four types of things taken three at a time. We can generalise this as follows. We can try to construct a code with the following properties: (1) Pour types of letters: A, B, C, and D. (2) Each sequence of three consecutive letters has a meaning (3) Overlapping i.e. DABDC means DAB .. then a BD then BDC etc. (k) A particular amino acid is represented by one or more sets of three letters, chosen at will . ,To illustrate, consider an unlikely code: The combination code There are 20 different combinations of four types of thing chosen three at a time (Note that Gamow's 20 comes from twice-ten, where ten is the number of combinations of four types of thing taken two at. a time). Thus one amino acid, say a, would be represented by the permutations: ABC, ACB, BAC, BC a , CAB and CBA. Another, say b, by BBD, BDB, DBB, and a third, say v, by CCC only.