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Solution nuclear magnetic resonance structure of membrane-integral diacylglycerol kinase.

ABSTRACT: Escherichia coli diacylglycerol kinase (DAGK) represents a family of integral membrane enzymes that is unrelated to all other phosphotransferases. We have determined the three-dimensional structure of the DAGK homotrimer with the use of solution nuclear magnetic resonance. The third transmembrane helix from each subunit is domain-swapped with the first and second transmembrane segments from an adjacent subunit. Each of DAGK's three active sites resembles a portico. The cornice of the portico appears to be the determinant of DAGK's lipid substrate specificity and overhangs the site of phosphoryl transfer near the water-membrane interface. Mutations to cysteine that caused severe misfolding were located in or near the active site, indicating a high degree of overlap between sites responsible for folding and for catalysis.

SUBMITTER: Van Horn WD

PROVIDER: S-EPMC2764269 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Solution nuclear magnetic resonance structure of membrane-integral diacylglycerol kinase.

Van Horn Wade D WD Kim Hak-Jun HJ Ellis Charles D CD Hadziselimovic Arina A Sulistijo Endah S ES Karra Murthy D MD Tian Changlin C Sönnichsen Frank D FD Sanders Charles R CR

Science (New York, N.Y.) 20090601 5935

Escherichia coli diacylglycerol kinase (DAGK) represents a family of integral membrane enzymes that is unrelated to all other phosphotransferases. We have determined the three-dimensional structure of the DAGK homotrimer with the use of solution nuclear magnetic resonance. The third transmembrane helix from each subunit is domain-swapped with the first and second transmembrane segments from an adjacent subunit. Each of DAGK's three active sites resembles a portico. The cornice of the portico app ...[more]

PMID: 19556511

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