title: Friend or foe: the same fold for attack and defense.
abstract: Two recent crystal structures of membrane attack complex/perforin (MACPF) domains found in the complement and perforin families unexpectedly reveal that some proteins of the immune system share a common core fold with their bacterial targets. Although a relationship between MACPF proteins and the previously characterized bacterial cholesterol-dependent cytolysins (CDCs) is not detectable by sequence analysis, the MACPF structures show that eukaryotic defense and bacterial CDC attack share a common mechanism of membrane insertion and pore formation.
authors.affiliation: Department of Crystallography and Institute of Structural Molecular Biology, Birkbeck College, London, UK.
authors.forename: Natalya
authors.initials: N
authors.lastname: Lukoyanova
authors.forename: Helen R
authors.initials: HR
authors.lastname: Saibil
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D015938:Complement Membrane Attack Complex / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D003165:Complement System Proteins / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D018360:Crystallography, X-Ray; D003603:Cytotoxins / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D006460:Hemolysin Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D007107:Immune System; D054353:Perforin / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D052899:Pore Forming Cytotoxic Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D017510:Protein Folding
chemical_list: D001427:Bacterial Toxins; D015938:Complement Membrane Attack Complex; D003603:Cytotoxins; D006460:Hemolysin Proteins; D052899:Pore Forming Cytotoxic Proteins; D054353:Perforin; C020452:Clostridium perfringens theta-toxin; D003165:Complement System Proteins