Dual granule localization of the dormant NADPH oxidase and cytochrome b559 in human neutrophils.
The subcellular localization of the microbicidal nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and associated b-cytochrome was investigated in human neutrophils. In unperturbed neutrophils 85% of b-cytochrome and the major part of membrane-bound components of the NADPH oxidase co-sedimented with markers for specific granules and gelatinase. Using cytochrome b559 as a marker for membrane-bound components of the NADPH oxidase in quantitative studies we observed that, of the remaining 15%, the vast majority co-sedimented with latent alkaline phosphatase, a marker for a newly identified mobilizable intracellular compartment. Only a small fraction co-localized with the plasma membranes. Azurophil granules contained a protease activity which rapidly inactivated the NADPH oxidase components present in other membranes. Stimulation of the neutrophils with formyl-methionyl-leucyl-phenyl-alanine and leukotriene B4 which caused minimal degranulation of specific granules, resulted in translocation of b-cytochrome to the plasma membrane, concomitant with incorporation of alkaline phosphatase into the plasma membrane.
Bjerrum
O W
OW
Department of Internal Medicine and Haematology C, University of Copenhagen, Gentofte Hospital, Hellerup, Denmark.
Borregaard
N
N
D000469:Alkaline Phosphatase / Q000378:metabolism; D002458:Cell Fractionation; D002462:Cell Membrane / Q000032:analysis / Q000378:metabolism; D002499:Centrifugation, Density Gradient; D003573:Cytochrome b Group / Q000032:analysis* / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000032:analysis* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007975:Leukotriene B4 / Q000494:pharmacology; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009247:NADH, NADPH Oxidoreductases / Q000032:analysis* / Q000378:metabolism; D019255:NADPH Oxidases; D009504:Neutrophils / Q000187:drug effects / Q000648:ultrastructure*; D045332:Photosystem II Protein Complex
D003573:Cytochrome b Group; D045332:Photosystem II Protein Complex; D007975:Leukotriene B4; D009240:N-Formylmethionine Leucyl-Phenylalanine; C019313:cytochrome b559; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D000469:Alkaline Phosphatase