National Center for
2HMF: Structure Of A Threonine Sensitive Aspartokinase From Methanococcus Jannaschii Complexed With Mg-adp And Aspartate
The initial step in the archaeal aspartate biosynthetic pathway catalyzed by a monofunctional aspartokinase
Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. (2006) 62 p.962-966
The activation of the beta-carboxyl group of aspartate catalyzed by aspartokinase is the commitment step to amino-acid biosynthesis in the aspartate pathway. The first structure of a microbial aspartokinase, that from Methanococcus jannaschii, has been determined in the presence of the amino-acid substrate L-aspartic acid and the nucleotide product MgADP. The enzyme assembles into a dimer of dimers, with the interfaces mediated by both the N- and C-terminal domains. The active-site functional groups responsible for substrate binding and specificity have been identified and roles have been proposed for putative catalytic functional groups.