2011
Molecular Structure and Biological Activity of NPP-4, An Endothelial Cell Surface Pyrophosphatase/ Phosphodiesterase That Stimulates Platelet Aggregation and Secretion Via Liberation of ADP Upon Hydrolysis of Diadenosine Triphosphate
Ornstein D, Albright R, Chang W, Robert D, Cao W, De La Cruz E, Braddock D. Molecular Structure and Biological Activity of NPP-4, An Endothelial Cell Surface Pyrophosphatase/ Phosphodiesterase That Stimulates Platelet Aggregation and Secretion Via Liberation of ADP Upon Hydrolysis of Diadenosine Triphosphate. Blood 2011, 118: 701. DOI: 10.1182/blood.v118.21.701.701.Peer-Reviewed Original ResearchHigh-resolution structuresActive site threonineDense granule releaseDiadenosine triphosphateExtracellular spaceNanomolar concentrationsEnzyme familyPlatelet dense granulesMolecular foundationMolecular basisExtracellular enzymesStructural basisPhosphodiesterase enzyme familyGranule releaseEnzymatic mechanismCell surfaceRapid disaggregationEndothelial cell surfaceDense granulesPlatelet aggregationAp3AEnzymatic productBiological activityConcentration-dependent fashionADP
1998
Structure−Function Relationships in Side Chain Lactam Cross-Linked Peptide Models of a Conserved N-Terminal Domain of Apolipoprotein E †
Benzinger T, Braddock D, Dominguez S, Burkoth T, Miller-Auer H, Subramanian R, Fless G, Jones D, Lynn D, Meredith S. Structure−Function Relationships in Side Chain Lactam Cross-Linked Peptide Models of a Conserved N-Terminal Domain of Apolipoprotein E †. Biochemistry 1998, 37: 13222-13229. PMID: 9748329, DOI: 10.1021/bi980482f.Peer-Reviewed Original ResearchMeSH KeywordsAmino Acid SequenceAnimalsApolipoproteins ECell LineCircular DichroismConserved SequenceEmbryo, MammalianFibroblastsIodine RadioisotopesLactamsMiceModels, MolecularMolecular Sequence DataNuclear Magnetic Resonance, BiomolecularPeptide FragmentsProtein Structure, SecondaryReceptors, LDLStructure-Activity RelationshipConceptsPeptide IVPeptide modelsConformational switchSide chain lactamLipid surfaceSide chainsBioactive peptidesStructural orderMultiple conformationsBiological activityStructure-function relationshipsLactamsAlpha-helixStrategic modificationsSecondary structureHelical segmentsPeptide IIIConformationAlpha-helical segmentsShort alpha helixCOOHHelixAntipodeStructureSolution
1994
Structural and thermodynamic characterization of a bioactive peptide model of apolipoprotein E: side-chain lactam bridges to constrain the conformation.
Luo P, Braddock D, Subramanian R, Meredith S, Lynn D. Structural and thermodynamic characterization of a bioactive peptide model of apolipoprotein E: side-chain lactam bridges to constrain the conformation. Biochemistry 1994, 33: 12367-77. PMID: 7918459, DOI: 10.1021/bi00207a003.Peer-Reviewed Original ResearchConceptsSide-chain lactam bridgePeptide modelsAlpha-helical peptidesLoss of entropyModel peptidesBioactive structuresNMR dataAlpha-helical structureLactam constraintsConformational flexibilityLactam bridgeKcal/Thermodynamic characterizationAlpha-helical domainBiological activityPlasma lipoprotein clearanceUnfolded stateCell surface receptorsBiological functionsPeptidesSurface receptorsStructureResiduesCentral bendCritical role