title: Isolation and characterization of rabbit properdin of the alternative complement pathway.
abstract: Rabbit factor P, which is involved in stabilizing the labile C3 convertase of the alternative complement pathway, was isolated from rabbit serum by a simple two-step procedure: polyethylene glycol precipitation and QAE-Sephadex A-50 column chromatography. The chemical properties, and functional activities of the rabbit P were very similar to those of human P, except that there were slight differences in the SDS-PAGE patterns of limited tryptic digests and in the amino terminal sequences. The molecular weights were estimated to be 58 000 for rabbit P and 59 000 for human P on SDS-PAGE under reducing conditions. The amino terminal 36 residues of rabbit P showed 78% homology to the equivalent region of human P.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002850:Chromatography, Gel; D003167:Complement Activation; D050577:Complement C3-C5 Convertases / Q000378:metabolism; D003170:Complement Pathway, Alternative; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008970:Molecular Weight; D011414:Properdin / Q000302:isolation & purification* / Q000502:physiology; D011817:Rabbits / Q000097:blood* / Q000276:immunology; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
chemical_list: D011414:Properdin; D050577:Complement C3-C5 Convertases