title: p47phox molecular activation for assembly of the neutrophil NADPH oxidase complex.
abstract: The p47(phox) cytosolic factor from neutrophilic NADPH oxidase has always been resistant to crystallogenesis trials due to its modular organization leading to relative flexibility. Hydrogen/deuterium exchange coupled to mass spectrometry was used to obtain structural information on the conformational mechanism that underlies p47(phox) activation. We confirmed a relative opening of the protein with exposure of the SH3 Src loops that are known to bind p22(phox) upon activation. A new surface was shown to be unmasked after activation, representing a potential autoinhibitory surface that may block the interaction of the PX domain with the membrane in the resting state. Within this surface, we identified 2 residues involved in the interaction with the PX domain. The double mutant R162A/D166A showed a higher affinity for specific phospholipids but none for the C-terminal part of p22(phox), reflecting an intermediate conformation between the autoinhibited and activated forms.
authors.affiliation: Laboratoire des Protéines Membranaires, Institut de Biologie Structurale (IBS), 41 rue Jules Horowitz, Grenoble, F-38027, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Marcoux
authors.forename: Petr
authors.initials: P
authors.lastname: Man
authors.forename: Isabelle
authors.initials: I
authors.lastname: Petit-Haertlein
authors.forename: Corinne
authors.initials: C
authors.lastname: Vivès
authors.forename: Eric
authors.initials: E
authors.lastname: Forest
authors.forename: Franck
authors.initials: F
authors.lastname: Fieschi
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D004789:Enzyme Activation / Q000502:physiology; D006801:Humans; D020125:Mutation, Missense; D019255:NADPH Oxidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009504:Neutrophils / Q000201:enzymology*; D017433:Protein Structure, Secondary; D018909:src Homology Domains
chemical_list: D019255:NADPH Oxidases; C086986:CYBA protein, human; C060505:neutrophil cytosolic factor 1