N5-CAIR mutase: role of a CO2 binding site and substrate movement in catalysis.
Hoskins, A.A., Morar, M., Kappock, T.J., Mathews, I.I., Zaugg, J.B., Barder, T.E., Peng, P., Okamoto, A., Ealick, S.E., Stubbe, J.(2007) Biochemistry 46: 2842-2855
- PubMed: 17298082 
- DOI: 10.1021/bi602436g
- Primary Citation of Related Structures:  
2ATE, 2NSH, 2NSJ, 2NSL - PubMed Abstract: 
N5-Carboxyaminoimidazole ribonucleotide mutase (N5-CAIR mutase or PurE) from Escherichia coli catalyzes the reversible interconversion of N5-CAIR to carboxyaminoimidazole ribonucleotide (CAIR) with direct CO2 transfer. Site-directed mutagenesis, a pH-rate profile, DFT calculations, and X-ray crystallography together provide new insight into the mechanism of this unusual transformation ...