Crystal structures that suggest late development of genetic code components for differentiating aromatic side chains
Yang, X.-L., Otero, F.J., Skene, R.J., McRee, D.E., Schimmel, P., Ribas De Pouplana, L.(2003) Proc Natl Acad Sci U S A 100: 15376-15380
- PubMed: 14671330 
- DOI: 10.1073/pnas.2136794100
- Primary Citation of Related Structures:  
1Q11, 1R6T - PubMed Abstract: 
Early forms of the genetic code likely generated "statistical" proteins, with similar side chains occupying the same sequence positions at different ratios. In this scenario, groups of related side chains were treated by aminoacyl-tRNA synthetases as a single molecular species until a discrimination mechanism developed that could separate them ...