Structure and mechanism of glutamate racemase from Aquifex pyrophilus.
Hwang, K.Y., Cho, C.S., Kim, S.S., Sung, H.C., Yu, Y.G., Cho, Y.(1999) Nat Struct Biol 6: 422-426
- PubMed: 10331867 
- DOI: https://doi.org/10.1038/8223
- Primary Citation of Related Structures:  
1B73, 1B74 - PubMed Abstract: 
Glutamate racemase (MurI) is responsible for the synthesis of D-glutamate, an essential building block of the peptidoglycan layer in bacterial cell walls. The crystal structure of glutamate racemase from Aquifex pyrophilus, determined at 2.3 A resolution, reveals that the enzyme forms a dimer and each monomer consists of two alpha/beta fold domains, a unique structure that has not been observed in other racemases or members of an enolase superfamily. A substrate analog, D-glutamine, binds to the deep pocket formed by conserved residues from two monomers. The structural and mutational analyses allow us to propose a mechanism of metal cofactor-independent glutamate racemase in which two cysteine residues are involved in catalysis.
Organizational Affiliation: 
Structural Biology Center, Korea Institute of Science and Technology, Seoul, South Korea.