title: Channel-forming bacterial toxins in biosensing and macromolecule delivery.
abstract: To intoxicate cells, pore-forming bacterial toxins are evolved to allow for the transmembrane traffic of different substrates, ranging from small inorganic ions to cell-specific polypeptides. Recent developments in single-channel electrical recordings, X-ray crystallography, protein engineering, and computational methods have generated a large body of knowledge about the basic principles of channel-mediated molecular transport. These discoveries provide a robust framework for expansion of the described principles and methods toward use of biological nanopores in the growing field of nanobiotechnology. This article, written for a special volume on "Intracellular Traffic and Transport of Bacterial Protein Toxins", reviews the current state of applications of pore-forming bacterial toxins in small- and macromolecule-sensing, targeted cancer therapy, and drug delivery. We discuss the electrophysiological studies that explore molecular details of channel-facilitated protein and polymer transport across cellular membranes using both natural and foreign substrates. The review focuses on the structurally and functionally different bacterial toxins: gramicidin A of Bacillus brevis, α-hemolysin of Staphylococcus aureus, and binary toxin of Bacillus anthracis, which have found their "second life" in a variety of developing medical and technological applications.
authors.affiliation: Physics Department, University of Massachusetts, Amherst, MA 01003, USA. gurnev@physics.umass.edu.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Gurnev
authors.affiliation: Department of Biology, the Catholic University of America, Washington, DC 20064, USA. nestorovich@cua.edu.
authors.forename: Ekaterina M
authors.initials: EM
authors.lastname: Nestorovich
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism / Q000627:therapeutic use; D001427:Bacterial Toxins / Q000378:metabolism / Q000627:therapeutic use; D001692:Biological Transport; D015374:Biosensing Techniques; D016503:Drug Delivery Systems; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy; D052899:Pore Forming Cytotoxic Proteins / Q000378:metabolism / Q000627:therapeutic use
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D052899:Pore Forming Cytotoxic Proteins