PMID:17872444

From EcoliWiki
Jump to navigation Jump to search
Citation

Hadders, MA, Beringer, DX and Gros, P (2007) Structure of C8alpha-MACPF reveals mechanism of membrane attack in complement immune defense. Science 317:1552-4

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.

Links

PubMed Online version:10.1126/science.1147103

Keywords

Amino Acid Sequence; Cell Membrane/immunology; Cell Membrane/metabolism; Complement C8/chemistry; Complement C8/immunology; Complement C8/metabolism; Complement Membrane Attack Complex/chemistry; Complement Membrane Attack Complex/immunology; Complement Membrane Attack Complex/metabolism; Crystallography, X-Ray; Cytotoxins/chemistry; Cytotoxins/metabolism; Humans; Hydrophobic and Hydrophilic Interactions; Membrane Glycoproteins/chemistry; Membrane Glycoproteins/metabolism; Models, Molecular; Molecular Sequence Data; Perforin; Pore Forming Cytotoxic Proteins/chemistry; Pore Forming Cytotoxic Proteins/metabolism; Protein Conformation; Protein Folding; Protein Structure, Secondary; Protein Structure, Tertiary

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.