title: Activation of cyclic nucleotide phosphodiesterase by a monosaccharide precursor of Escherichia coli lipid A.
abstract: The E. coli lipid A precursor lipid X (N2,O3-diacylglucosamine 1-phosphate) activates calmodulin-dependent cyclic nucleotide phosphodiesterase in a noncooperative, calcium-independent manner by increasing its Vmax and decreasing its Km for substrate. The glycolipid produces half-maximal activation at 11 micrograms/ml and does not further enhance activation by calcium-calmodulin. Lipid X activation of phosphodiesterase requires the presence of the O3-linked hydroxymyristoyl residue. These findings suggest that lipid X could produce some of its biological effects by modulating intracellular cAMP levels.
authors.affiliation: College of Dentistry, Ohio State University, Columbus 43210.
authors.forename: J D
authors.initials: JD
authors.lastname: Walters
authors.forename: R C
authors.initials: RC
authors.lastname: Jirsa
mesh_terms: D019703:Calcineurin; D002118:Calcium / Q000494:pharmacology; D002147:Calmodulin / Q000378:metabolism* / Q000494:pharmacology; D002148:Calmodulin-Binding Proteins / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D004926:Escherichia coli; D006017:Glycolipids / Q000494:pharmacology*; D008050:Lipid A; D009005:Monosaccharides / Q000494:pharmacology*; D010749:Phosphoprotein Phosphatases / Q000494:pharmacology; D013329:Structure-Activity Relationship
chemical_list: D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D006017:Glycolipids; D008050:Lipid A; D009005:Monosaccharides; C044283:lipid X; D019703:Calcineurin; D010749:Phosphoprotein Phosphatases; D002118:Calcium