Purification and physical properties of a novel type of cytochrome b from rabbit peritoneal neutrophils.

摘要: Abstract The main redox component of the O2- generating oxidase complex in neutrophils is believed to be a b-type cytochrome, named cytochrome b558. In course purification b558 from rabbit peritoneal neutrophils, another hemoprotein with an apparent molecular mass 30 kDa, referred as p-30, was isolated. Although spectrum p-30 virtually identical that b558, its potential, Em,7 = -4 +/- 10 mV, much less negative than (-270 5 mV). alkaline pyridine hemochrome purified typical cytochrome. 20 N-terminal amino acid residues and some tryptic peptides isolated did not show any significant sequence homology human phagocyte or mitochondrial microsomal cytochromes, except for region which displayed rat liver P-450. After subcellular fractionation, found located plasma membrane granule fractions, similarly Upon neutrophil activation, part transferred granules membrane.