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The initial step in the archaeal aspartate biosynthetic pathway catalyzed by a monofunctional aspartokinase.

ABSTRACT: 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.

SUBMITTER: Faehnle CR

PROVIDER: S-EPMC2225177 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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The initial step in the archaeal aspartate biosynthetic pathway catalyzed by a monofunctional aspartokinase.

Faehnle Christopher R CR Liu Xuying X Pavlovsky Alexander A Viola Ronald E RE

Acta crystallographica. Section F, Structural biology and crystallization communications 20060930 Pt 10

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 gr ...[more]

PMID: 17012784

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