title: Microbiological and molecular assessment of bacteriophage ISP for the control of Staphylococcus aureus.
abstract: The increasing antibiotic resistance in bacterial populations requires alternatives for classical treatment of infectious diseases and therefore drives the renewed interest in phage therapy. Methicillin resistant Staphylococcus aureus (MRSA) is a major problem in health care settings and live-stock breeding across the world. This research aims at a thorough microbiological, genomic, and proteomic characterization of S. aureus phage ISP, required for therapeutic applications. Host range screening of a large batch of S. aureus isolates and subsequent fingerprint and DNA microarray analysis of the isolates revealed a substantial activity of ISP against 86% of the isolates, including relevant MRSA strains. From a phage therapy perspective, the infection parameters and the frequency of bacterial mutations conferring ISP resistance were determined. Further, ISP was proven to be stable in relevant in vivo conditions and subcutaneous as well as nasal and oral ISP administration to rabbits appeared to cause no adverse effects. ISP encodes 215 gene products on its 138,339 bp genome, 22 of which were confirmed as structural proteins using tandem electrospray ionization-mass spectrometry (ESI-MS/MS), and shares strong sequence homology with the 'Twort-like viruses'. No toxic or virulence-associated proteins were observed. The microbiological and molecular characterization of ISP supports its application in a phage cocktail for therapeutic purposes.
authors.affiliation: Division of Gene Technology, Katholieke Universiteit Leuven, Heverlee, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: Vandersteegen
authors.forename: Wesley
authors.initials: W
authors.lastname: Mattheus
authors.forename: Pieter-Jan
authors.initials: PJ
authors.lastname: Ceyssens
authors.forename: Florence
authors.initials: F
authors.lastname: Bilocq
authors.forename: Daniel
authors.initials: D
authors.lastname: De Vos
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Pirnay
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Noben
authors.forename: Maia
authors.initials: M
authors.lastname: Merabishvili
authors.forename: Urszula
authors.initials: U
authors.lastname: Lipinska
authors.forename: Katleen
authors.initials: K
authors.lastname: Hermans
authors.forename: Rob
authors.initials: R
authors.lastname: Lavigne
mesh_terms: D000818:Animals; D001435:Bacteriophages / Q000235:genetics*; D055592:Biophysical Phenomena; D019295:Computational Biology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D016679:Genome, Viral / Q000235:genetics; D005838:Genotype; D058507:Host Specificity / Q000235:genetics; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000821:virology; D010802:Phylogeny; D020543:Proteome / Q000378:metabolism; D011817:Rabbits; D021241:Spectrometry, Mass, Electrospray Ionization; D013203:Staphylococcal Infections / Q000382:microbiology* / Q000517:prevention & control*; D013211:Staphylococcus aureus / Q000235:genetics / Q000821:virology*; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism; D014771:Virion / Q000235:genetics / Q000378:metabolism
chemical_list: D020543:Proteome; D014764:Viral Proteins