Abstract
Isolation of the C5b-9 complex from inulin-activated whole human serum was effected by molecular sieve column chromatography employing Biogel A-15 M, preparative Pevikon block electrophoresis, and removal of low density beta-lipoproteins by flotation in CsCl. The final product was homogeneous upon cellulose acetate strip electrophoresis and analytical ultracentrifugation. Ouchterlony analyses indicated that the complex reacted with antisera to C5, C6, C7, C8, and C9 to form a continuous, circular precipitin line without spurs. The C5b-9 complex was dissociated by sodium dodecyl sulfate (SDS) in the absence of reducing agents, and analytical SDS-polyacrylamide gel electrophoresis revealed seven protein bands after straining with Coomassie Blue. Bands 1, 2, 3, and 6 were identified as C5b, C7, C6, and C9, respectively. Bands 4 and 7 were identified as two noncovalently bound subunits of C8. Molar ratios among C5b, C6, C7, C8, and C9 dissociated from the complex by SDS were estimated to be 1:1:1:1:3. Band 5 protein, which had an estimated mol wt of 88,000 and was found to occur with a molar ratio of 3, has not yet been identified. Its nature and possible biological functions are discussed.
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- Arroyave C. M., Müller-Eberhard H. J. Isolation of the sixth component of complement from human serum. Immunochemistry. 1971 Nov;8(11):995–1006. doi: 10.1016/0019-2791(71)90487-3. [DOI] [PubMed] [Google Scholar]
- Hadding U., Müller-Eberhard H. J. The ninth component of human complement: isolation, description and mode of action. Immunology. 1969 Jun;16(6):719–735. [PMC free article] [PubMed] [Google Scholar]
- Kolb W. P., Haxby J. A., Arroyave C. M., Müller-Eberhard H. J. Molecular analysis of the membrane attack mechanism of complement. J Exp Med. 1972 Mar 1;135(3):549–566. doi: 10.1084/jem.135.3.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kolb W. P., Müller-Eberhard H. J. The membrane attack mechanism of complement. Verification of a stable C5-9 complex in free solution. J Exp Med. 1973 Aug 1;138(2):438–451. doi: 10.1084/jem.138.2.438. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Lachmann P. J., Müller-Eberhard H. J. The demonstration in human serum of "conglutinogen-activating factor" and its effect on the third component of complement. J Immunol. 1968 Apr;100(4):691–698. [PubMed] [Google Scholar]
- Manni J. A., Müller-Eberhard H. J. The eighth component of human complement (C8): isolation, characterization, and hemolytic efficiency. J Exp Med. 1969 Nov 1;130(5):1145–1160. doi: 10.1084/jem.130.5.1145. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McConahey P. J., Dixon F. J. A method of trace iodination of proteins for immunologic studies. Int Arch Allergy Appl Immunol. 1966;29(2):185–189. doi: 10.1159/000229699. [DOI] [PubMed] [Google Scholar]
- NILSSON U. R., MUELLER-EBERHARD H. J. ISOLATION OF BETA IF-GLOBULIN FROM HUMAN SERUM AND ITS CHARACTERIZATION AS THE FIFTH COMPONENT OF COMPLEMENT. J Exp Med. 1965 Aug 1;122:277–298. doi: 10.1084/jem.122.2.277. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nelson R. A., Jr, Jensen J., Gigli I., Tamura N. Methods for the separation, purification and measurement of nine components of hemolytic complement in guinea-pig serum. Immunochemistry. 1966 Mar;3(2):111–135. doi: 10.1016/0019-2791(66)90292-8. [DOI] [PubMed] [Google Scholar]
- Nilsson U. R., Tomar R. H., Taylor F. B., Jr Additional studies on human C5: development of a modified purification method and characterization of the purified product by polyacrylamide gel electrophoresis. Immunochemistry. 1972 Jul;9(7):709–723. doi: 10.1016/0019-2791(72)90015-8. [DOI] [PubMed] [Google Scholar]
- Ruddy S., Austen K. F. C3b inactivator of man. II. Fragments produced by C3b inactivator cleavage of cell-bound or fluid phase C3b. J Immunol. 1971 Sep;107(3):742–750. [PubMed] [Google Scholar]
- Weber K., Osborn M. The reliability of molecular weight determinations by dodecyl sulfate-polyacrylamide gel electrophoresis. J Biol Chem. 1969 Aug 25;244(16):4406–4412. [PubMed] [Google Scholar]