title: Structure and function of pore-forming beta-barrels from bacteria.
abstract: Crystallographic studies of the past ten years have revealed that many outer membrane proteins and bacterial toxins are constructed on the beta-barrel motif. Two structural classes can be identified. The first class, represented by the porins, includes monomeric or multimeric proteins where each beta-barrel is formed from a single polypeptide. The second class features proteins where the beta-barrel is itself a multimeric assembly, to which each subunit contributes a few beta-strands. In addition to structural investigations, much work has also been devoted to the functional aspects of these proteins, and to the relationships between structure and function. Here we present a review of the structural and the functional properties of some of the best-studied examples of these various classes of proteins, namely the general-diffusion, specific and ligand-gated porins, multidrug efflux proteins and the staphylococcal toxin alpha-hemolysin.
authors.affiliation: Department of Biology and Biochemistry, University of Houston, TX 77204-5001, USA. adelcour@uh.edu
authors.forename: Anne H
authors.initials: AH
authors.lastname: Delcour
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000502:physiology; D001427:Bacterial Toxins / Q000737:chemistry; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry / Q000502:physiology; D006460:Hemolysin Proteins / Q000737:chemistry / Q000502:physiology; D015640:Ion Channel Gating; D008024:Ligands; D008958:Models, Molecular; D018272:Porins / Q000737:chemistry* / Q000502:physiology*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D021122:Protein Subunits
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D008024:Ligands; D018272:Porins; D021122:Protein Subunits; C021091:staphylococcal alpha-toxin; C078167:OMPA outer membrane proteins