Recognition of Watson-Crick base pairs: constraints and limits due to geometric selection and tautomerism.
The natural bases of nucleic acids have a strong preference for one tautomer form, guaranteeing fidelity in their hydrogen bonding potential. However, base pairs observed in recent crystal structures of polymerases and ribosomes are best explained by an alternative base tautomer, leading to the formation of base pairs with Watson-Crick-like geometries. These observations set limits to geometric selection in molecular recognition of complementary Watson-Crick pairs for fidelity in replication and translation processes.
Architecture et Réactivité de l'ARN, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire CNRS, 15 rue René Descartes, F-67084 Strasbourg Cedex France.
Eric
E
Westhof
Département de Biologie et de Génomique Structurales, Institut de Génétique et de Biologie Moléculaire et Cellulaire CNRS, INSERM, Université de Strasbourg, F-67400 Illkirch France.
Marat
M
Yusupov
Département de Biologie et de Génomique Structurales, Institut de Génétique et de Biologie Moléculaire et Cellulaire CNRS, INSERM, Université de Strasbourg, F-67400 Illkirch France.
Gulnara
G
Yusupova