1o7k
From Proteopedia
human p47 PX domain complex with sulphates
Structural highlights
DiseaseNCF1_HUMAN Defects in NCF1 are the cause of chronic granulomatous disease autosomal recessive cytochrome-b-positive type 1 (CGD1) [MIM:233700. Chronic granulomatous disease is a genetically heterogeneous disorder characterized by the inability of neutrophils and phagocytes to kill microbes that they have ingested. Patients suffer from life-threatening bacterial/fungal infections.[1] [2] FunctionNCF1_HUMAN NCF2, NCF1, and a membrane bound cytochrome b558 are required for activation of the latent NADPH oxidase (necessary for superoxide production).[3] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedp47(phox) is a key cytosolic subunit required for activation of phagocyte NADPH oxidase. The X-ray structure of the p47(phox) PX domain revealed two distinct basic pockets on the membrane-binding surface, each occupied by a sulfate. These two pockets have different specificities: one preferentially binds phosphatidylinositol 3,4-bisphosphate [PtdIns(3,4)P(2)] and is analogous to the phophatidylinositol 3-phosphate (PtdIns3P)-binding pocket of p40(phox), while the other binds anionic phospholipids such as phosphatidic acid (PtdOH) or phosphatidylserine. The preference of this second site for PtdOH may be related to previously observed activation of NADPH oxidase by PtdOH. Simultaneous occupancy of the two phospholipid-binding pockets radically increases membrane affinity. Strikingly, measurements for full-length p47(phox) show that membrane interaction by the PX domain is masked by an intramolecular association with the C-terminal SH3 domain (C-SH3). Either a site-specific mutation in C-SH3 (W263R) or a mimic of the phosphorylated form of p47(phox) [Ser(303, 304, 328, 359, 370)Glu] cause a transition from a closed to an open conformation that binds membranes with a greater affinity than the isolated PX domain. Binding of the PX domain of p47(phox) to phosphatidylinositol 3,4-bisphosphate and phosphatidic acid is masked by an intramolecular interaction.,Karathanassis D, Stahelin RV, Bravo J, Perisic O, Pacold CM, Cho W, Williams RL EMBO J. 2002 Oct 1;21(19):5057-68. PMID:12356722[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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