Recognition of flanking DNA sequences by EcoRV endonuclease involves alternative patterns of water-mediated contacts.
Horton, N.C., Perona, J.J.(1998) J Biological Chem 273: 21721-21729
- PubMed: 9705308 
- DOI: https://doi.org/10.1074/jbc.273.34.21721
- Primary Citation of Related Structures:  
1BGB - PubMed Abstract: 
The 2.1-A cocrystal structure of EcoRV endonuclease bound to 5'-CGGGATATCCC, in a crystal lattice isomorphous with the cocrystallized undecamer 5'-AAAGATATCTT previously determined, shows novel base recognition in the major groove of the DNA flanking the GATATC target site. Lys104 of the enzyme interacts through water molecules with the exocyclic N-4 amino groups of flanking cytosines. Steric exclusion of water molecule-binding sites by the 5-methyl group of thymine drives the adoption of alternative water-mediated contacts with AT versus GC flanks. This structure provides a rare example of structural adaptability in the recognition of different DNA sequences by a protein and suggests preferred strategies for the expansion of target site specificity by EcoRV.
Organizational Affiliation: 
Department of Chemistry and Interdepartmental Program in Biochemistry and Molecular Biology, University of California, Santa Barbara, California 93106-9510, USA.