Monoheme cytochrome whose physiological function is not yet clear. Binds 1 heme group per subunit. E(0) is >350 mV. N-glycosylated on at least seven Asn residues by identical hexasaccharide units composed of Man, GlcNAc, Glc and 6-deoxy-6-sulfoglucose residues in the molar ration of 2:2:1:1. O-glycosylated on probably as many as 35 positions by single Man residues. Glycosylated.