It is suggested that protein synthesis may have begun without even a primitive ribosome if the primitive tRNA could take up two configurations and could bind to the messenger RNA with five base-pairs instead of the present three. This idea would impose base sequence restriction on the early messages and on the early genetic code such that the first four amino acids coded were glycine, serine, aspartic acid and aspargine. A possible mechanism is suggested for the polymerization of the early message.
KeywordsPolymerization Organic Chemistry Glycine Geochemistry Serine
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- Barell, B. G. and Clark, B. F. S.: 1974,Handbook of Nucleic Acid Sequences, Joynson-Bruvveri Ltd., Oxford.Google Scholar
- Crick, F. H. C.: 1966,J. Mol. Biol.,19, 584.Google Scholar
- Crick, F. H. C., Griffith, J. S., and Orgel, L. E.: 1957,Proc. Nat. Acad. Sci. (U.S.A.) 43, 416.Google Scholar
- Eigen, M.: 1973, in J. Mehra (ed.),The Physicist's Conception of Nature, D. Reidel Publishing Co., Boston, U.S.A.Google Scholar
- Woese, C. R.: 1967,The Genetic Code, Harper and Row, New York, Evanston and London.Google Scholar
- Woese, C. R.: 1972, in C. Ponnamperuma (ed.),Exobiology, North-Holland Publishing Co.Google Scholar