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Analysis of the Staphylococcus aureus DgkB structure reveals a common catalytic mechanism for the soluble diacylglycerol kinases.

ABSTRACT: Soluble diacylglycerol (DAG) kinases function as regulators of diacylglycerol metabolism in cell signaling and intermediary metabolism. We report the structure of a DAG kinase, DgkB from Staphylococcus aureus, both as the free enzyme and in complex with ADP. The molecule is a tight homodimer, and each monomer comprises two domains with the catalytic center located within the interdomain cleft. Two distinctive features of DkgB are a structural Mg2+ site and an associated Asp*water*Mg2+ network that extends toward the active site locale. Site-directed mutagenesis revealed that these features play important roles in the catalytic mechanism. The key active site residues and the components of the Asp*water*Mg2+ network are conserved in the catalytic cores of the mammalian signaling DAG kinases, indicating that these enzymes use the same mechanism and have similar structures as DgkB.

SUBMITTER: Miller DJ

PROVIDER: S-EPMC2847398 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Analysis of the Staphylococcus aureus DgkB structure reveals a common catalytic mechanism for the soluble diacylglycerol kinases.

Miller Darcie J DJ Jerga Agoston A Rock Charles O CO White Stephen W SW

Structure (London, England : 1993) 20080701 7

Soluble diacylglycerol (DAG) kinases function as regulators of diacylglycerol metabolism in cell signaling and intermediary metabolism. We report the structure of a DAG kinase, DgkB from Staphylococcus aureus, both as the free enzyme and in complex with ADP. The molecule is a tight homodimer, and each monomer comprises two domains with the catalytic center located within the interdomain cleft. Two distinctive features of DkgB are a structural Mg2+ site and an associated Asp*water*Mg2+ network th ...[more]

PMID: 18611377

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