A strategically positioned cation is crucial for efficient catalysis by chorismate mutase.
Kast, P., Grisostomi, C., Chen, I.A., Li, S., Krengel, U., Xue, Y., Hilvert, D.(2000) J Biol Chem 275: 36832-36838
- PubMed: 10960481 
- DOI: 10.1074/jbc.M006351200
- Primary Citation of Related Structures:  
1FNK, 1FNJ - PubMed Abstract: 
Combinatorial mutagenesis and in vivo selection experiments previously afforded functional variants of the AroH class Bacillus subtilis chorismate mutase lacking the otherwise highly conserved active site residue Arg(90). Here, we present a detailed kinetic and crystallographic study of several such variants ...