title: Structural and functional analogy between pneumolysin and proaerolysin.
abstract: Pneumolysin and proaerolysin are bacterial toxins that form pores in host cells by oligomerization. We propose that they may have similar structures despite a poor sequence identity. The crystal structure of proaerolysin reveals a protein composed of four domains, arranged in the shape of an elongated comma. Electron microscopy of the pneumolysin monomer shows a similar arrangement of domains. The sequence of pneumolysin recognizes the template of proaerolysin from a library of protein folds. A three-dimensional model of pneumolysin has been constructed by the comparative approach using the structure of proaerolysin. This model, together with results on the activity of site-specific mutants and the positions of antigenic sites, has been used to propose functional roles of individual domains.
authors.affiliation: Imperial Cancer Research Fund, Unit of Structural Molecular Biology, Department of Crystallography, Birkbeck College, UK.
authors.forename: R
authors.initials: R
authors.lastname: Sowdhamini
authors.forename: T J
authors.initials: TJ
authors.lastname: Mitchell
authors.forename: P W
authors.initials: PW
authors.lastname: Andrew
authors.forename: P J
authors.initials: PJ
authors.lastname: Morgan
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006460:Hemolysin Proteins / Q000737:chemistry; D008854:Microscopy, Electron; D008958:Models, Molecular; D008969:Molecular Sequence Data; D052899:Pore Forming Cytotoxic Proteins; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D012984:Software; D013301:Streptolysins / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D052899:Pore Forming Cytotoxic Proteins; D013301:Streptolysins; C032290:plY protein, Streptococcus pneumoniae; C107096:proaerolysin; C032676:aerolysin