Analysis of glycosylation sites on gp91phox, the flavocytochrome of the NADPH oxidase, by site-directed mutagenesis and translation in vitro.
Flavocytochrome b558 of the NADPH oxidase which generates superoxide in phagocytic cells, is a alpha1 beta1 heterodimer of gp91phox and p22phox, which together form a membrane-spanning electron-transport chain that transfers electrons from NADPH in the cytosol to oxygen. The C-terminal portion of gp91phox is a member of the ferredoxin-NADP+ reductase family of reductases. Little is known of the organization of the N-terminal section of this molecule, which is associated with the two haem structures. It is N-glycosylated, and site-directed mutagenesis has been used to eliminate the five potential N-linked glycosylation consensus sites. Mutated cDNAs were expressed in vitro. This approach provided evidence for glycosylation of residues Asn131, Asn148 and Asn239, but not of Asn96 and Asn429.
Wallach
T M
TM
Department of Medicine, University College London, U.K.
Segal
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AW
D003573:Cytochrome b Group / Q000737:chemistry*; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression / Q000235:genetics; D006031:Glycosylation; D006105:Granulomatous Disease, Chronic; D006801:Humans; D008562:Membrane Glycoproteins / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D009154:Mutation / Q000235:genetics; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000378:metabolism*; D010586:Phagocytes / Q000737:chemistry / Q000378:metabolism; D014176:Protein Biosynthesis / Q000235:genetics; D011487:Protein Conformation; D012156:Reticulocytes / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics
D003573:Cytochrome b Group; D017931:DNA Primers; D018076:DNA, Complementary; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; C036888:cytochrome b558; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases