title: Characterization of novelStaphylococcus aureuslytic phage and defining their combinatorial virulence using the OmniLog® system.
abstract: Skin and soft tissue infections (SSTI) caused by methicillin resistantStaphylococcus aureus(MRSA) are difficult to treat. Bacteriophage (phage) represent a potential alternate treatment for antibiotic resistant bacterial infections. In this study, 7 novel phage with broad lytic activity forS. aureuswere isolated and identified. Screening of a diverse collection of 170 clinical isolates by efficiency of plating (EOP) assays shows that the novel phage are virulent and effectively prevent growth of 70-91% of MRSA and methicillin sensitiveS. aureus(MSSA) isolates. Phage K, which was previously identified as having lytic activity onS. aureuswas tested on theS. aureuscollection and shown to prevent growth of 82% of the isolates. These novel phage group were examined by electron microscopy, the results of which indicate that the phage belong to theMyoviridaefamily of viruses. The novel phage group requires β-N-acetyl glucosamine (GlcNac) moieties on cell wall teichoic acids for infection. The phage were distinct from, but closely related to, phage K as characterized by restriction endonuclease analysis. Furthermore, growth rate analysis via OmniLog® microplate assay indicates that a combination of phage K, with phage SA0420ᶲ1, SA0456ᶲ1 or SA0482ᶲ1 have a synergistic phage-mediated lytic effect on MRSA and suppress formation of phage resistance. These results indicate that a broad spectrum lytic phage mixture can suppress the emergence of resistant bacterial populations and hence have great potential for combatingS. aureuswound infections.
authors.affiliation: Biological Defense Research Directorate, Naval Medical Research Center-Frederick , Fort Detrick, MD USA.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Estrella
authors.affiliation: Biological Defense Research Directorate, Naval Medical Research Center-Frederick , Fort Detrick, MD USA.
authors.forename: Javier
authors.initials: J
authors.lastname: Quinones
authors.affiliation: Biological Defense Research Directorate, Naval Medical Research Center-Frederick , Fort Detrick, MD USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Henry
authors.affiliation: National Biofoerensic Analysis and Countermeasures Center , Fort Detrick, Frederick, MD, USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Hannah
authors.affiliation: National Biofoerensic Analysis and Countermeasures Center , Fort Detrick, Frederick, MD, USA.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Pope
authors.affiliation: Biological Defense Research Directorate, Naval Medical Research Center-Frederick , Fort Detrick, MD USA.
authors.forename: Theron
authors.initials: T
authors.lastname: Hamilton
authors.affiliation: Wound Infections Department, Naval Medical Research Center-Silver Spring , Silver Spring, MD, USA.
authors.forename: Nimfa
authors.initials: N
authors.lastname: Teneza-Mora
authors.affiliation: Wound Infections Department, Naval Medical Research Center-Silver Spring , Silver Spring, MD, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Hall
authors.affiliation: Biological Defense Research Directorate, Naval Medical Research Center-Frederick , Fort Detrick, MD USA.
authors.forename: Biswas
authors.initials: B
authors.lastname: Biswajit
keywords: Staphylococcus aureus; bacteriophage; bacteriophage K; multi-drug resistance; teichoic acid