1. On the origin of the genetic code
Eörs Szathmáry
Collegium Budapest Eötvös University

2. The structure of the genetic code

3. Variants of the common code

4. Amino acid biosynthesis in E. coli

5. Coevolution chart Precursor-product pairs in biosynthesis
Dashed boxes are hypothetical intermediate stages
Italicised codons do not match coevolution predictions

6. Constraints on codon reshuffling for statistical investigations

7. 3 ways of code evolution

8. Forces may have changed in strength

9. Cofactor use by aptamers

10. From RNA to protein Gradual lose of scaffold
Amino acids to peptides to proteins
Not very well worked out

11. Piecewise evolution of tRNA

12. Proteins from pieces

13. Superfolds

14. Some more proteins

15. Ribosomal proteins cannot fold by themselves

16. Tryptophan-binding aptamers

17. The smallest typtophan binder
The anticodon is CCA
13 fully conserved nucleotides (26 bits of information)
Selective among hydrophobic changes

18. An interesting idea?
First two bases of a codon implied in synthesis of amino acids originating from the reductive citric acid cycle