title: Simple method for plating Escherichia coli bacteriophages forming very small plaques or no plaques under standard conditions.
abstract: The use of low concentrations (optimally 2.5 to 3.5 microg/ml, depending on top agar thickness) of ampicillin in the bottom agar of the plate allows for formation of highly visible plaques of bacteriophages which otherwise form extremely small plaques or no plaques on Escherichia coli lawns. Using this method, we were able to obtain plaques of newly isolated bacteriophages, propagated after induction of prophages present in six E. coli O157:H(-) strains which did not form plaques when standard plating procedures were employed.
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Kładki 24, 80-822 Gdańsk, Poland.
authors.forename: Joanna M
authors.initials: JM
authors.lastname: Loś
authors.forename: Piotr
authors.initials: P
authors.lastname: Golec
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Wegrzyn
authors.forename: Alicja
authors.initials: A
authors.lastname: Wegrzyn
authors.forename: Marcin
authors.initials: M
authors.lastname: Loś
mesh_terms: D000362:Agar; D000667:Ampicillin / Q000494:pharmacology*; D003090:Coliphages / Q000187:drug effects* / Q000254:growth & development*; D003470:Culture Media; D019453:Escherichia coli O157 / Q000821:virology*; D010948:Viral Plaque Assay / Q000379:methods*
chemical_list: D003470:Culture Media; D000667:Ampicillin; D000362:Agar