2QQH
Structure of C8a-MACPF reveals mechanism of membrane attack in complement immune defense
Summary for 2QQH
| Entry DOI | 10.2210/pdb2qqh/pdb |
| Descriptor | Complement component C8 alpha chain, SULFATE ION, NICKEL (II) ION, ... (4 entities in total) |
| Functional Keywords | macpf, membrane perforation, cleavage on pair of basic residues, complement alternate pathway, complement pathway, cytolysis, egf-like domain, glycoprotein, immune response, innate immunity, membrane attack complex, polymorphism, secreted, immune system, membrane protein |
| Biological source | Homo sapiens (human) More |
| Cellular location | Secreted: P07357 |
| Total number of polymer chains | 1 |
| Total formula weight | 37890.10 |
| Authors | Hadders, M.A.,Gros, P. (deposition date: 2007-07-26, release date: 2007-09-25, Last modification date: 2021-10-20) |
| Primary citation | Hadders, M.A.,Beringer, D.X.,Gros, P. Structure of C8alpha-MACPF reveals mechanism of membrane attack in complement immune defense. Science, 317:1552-1554, 2007 Cited by PubMed Abstract: Membrane attack is important for mammalian immune defense against invading microorganisms and infected host cells. Proteins of the complement membrane attack complex (MAC) and the protein perforin share a common MACPF domain that is responsible for membrane insertion and pore formation. We determined the crystal structure of the MACPF domain of complement component C8alpha at 2.5 angstrom resolution and show that it is structurally homologous to the bacterial, pore-forming, cholesterol-dependent cytolysins. The structure displays two regions that (in the bacterial cytolysins) refold into transmembrane beta hairpins, forming the lining of a barrel pore. Local hydrophobicity explains why C8alpha is the first complement protein to insert into the membrane. The size of the MACPF domain is consistent with known C9 pore sizes. These data imply that these mammalian and bacterial cytolytic proteins share a common mechanism of membrane insertion. PubMed: 17872444DOI: 10.1126/science.1147103 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.5 Å) |
Structure validation
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