title: Antimicrobial activity of a UV-stable bacteriocin-like inhibitory substance (BLIS) produced by Enterococcus faecium strain DSH20 against vancomycin-resistant Enterococcus (VRE) strains.
abstract: OBJECTIVE
  The narrow spectrum of action of most bacteriocins is an important limitation for their application as antimicrobial agents. The current study describes a novel bacteriocin-like inhibitory substance (BLIS) that display extended spectrum antimicrobial activity against vancomycin-resistant Enterococcus (VRE) strains.
  
  
  METHODS
  Acquired resistance profiles of Enterococcus isolates determined based on the European Centre for Disease Prevention and Control (ECDC) and the Centers for Disease Control and Prevention (CDC) definition as multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug resistant (PDR). BLIS activity of Enterococcus isolates was investigated against Enterococcus faecalis (E. faecalis) ATCC 29212 as the indicator strain and clinical isolates including VRE, methicillin resistant Staphylococcus aureus (MRSA) and Gram-negative bacteria containing Pseudomonas aeruginosa (P. aeruginosa), Klebsiella, Acinetobacter, and Escherichia coli (E. coli).
  
  
  RESULTS
  Among 273 Enterococcus isolates, 27 and 2 VRE isolates, respectively, were XDR and PDR and eight isolates had BLIS activity against the indicator strain. One of these isolates, identified as E. faecium strain DSH20 based on its phenotypical and biochemical properties, as well as its 16S rRNA gene sequence, had potent BLIS production against all 29 VRE strains, but had no activity against MRSA, P. aeruginosa, Klebsiella, Acinetobacter, and E. coli strains. It was heat stable up to 121°C for 15 minutes (autoclave condition), active within the pH range of 3-9 and had UV stability, but its activity disappeared by treatment with proteinase K, pepsin, and trypsin, demonstrating its proteinaceous nature. It was designated as an approximately 35kDa peptide using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method.
  
  
  CONCLUSIONS
  This peptide is a potential agent for use as an alternative antibacterial agent for the treatment of drug-resistant strains of VRE infection.
authors.affiliation: Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address: Dariush.shokri61@yahoo.com.
authors.forename: Dariush
authors.initials: D
authors.lastname: Shokri
authors.affiliation: Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran.
authors.forename: Saeideh
authors.initials: S
authors.lastname: Zaghian
authors.affiliation: Department of Pharmaceutical Biotechnology and Isfahan Pharmaceutical Sciences Research Center, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Khodabakhsh
authors.affiliation: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Fazeli
authors.affiliation: Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Sina
authors.initials: S
authors.lastname: Mobasherizadeh
authors.affiliation: Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Behrooz
authors.initials: B
authors.lastname: Ataei
mesh_terms: D001430:Bacteriocins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology* / Q000528:radiation effects; D024901:Drug Resistance, Multiple, Bacterial; D004355:Drug Stability; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D013696:Temperature; D065507:Vancomycin-Resistant Enterococci / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D001430:Bacteriocins
keywords: BLIS; Enterococcus faecium; Pandrug resistant (PDR); Vancomycin-resistant Enterococcus (VRE)