Publication details

Molecular characterization of a new efficiently transducing bacteriophage identified in methicillin-resistant Staphylococcus aureus

Authors

VARGA Marian DOŠKAŘ Jiří PANTŮČEK Roman

Year of publication 2013
Type Conference abstract
MU Faculty or unit

Faculty of Science

Citation
Description Temperate bacteriophages of Staphylococcus aureus play a major role in spreading mobile genetic elements among bacterial strains by transduction. This phenomenon leads to rapid evolution of the strains due to acquisition of antibiotic resistance genes and virulence factors. As a result, multiresistant strains of S. aureus insensitive to a broad spectrum of antimicrobial agents pose a significant threat to global health care system. In this work we characterized in detail a new, very efficiently transducing bacteriophage from methicillin-resistant S. aureus (MRSA) strain Jevons B. The bacteriophage, designated JB, was isolated from its host strain by UV induction to high titre and the phage lysate was used for transduction experiments. Whole-genome pyrosequencing of phage’s DNA was performed on Roche 454 GS FLX Titanium. Further, the DNA sequence was analyzed in silico to predict genes, regulatory elements, gene products’ functions and to find out homologies with other phage genes. Transmission electron microscopy was employed to visualize the shape of virions. Based on transduction experiments with laboratory S. aureus strains, and also the strains belonging to USA300 clone, we discovered that the phage efficiently transfers antibiotic resistance plasmids both directly after induction as well as after its propagation on donor strains. Restriction profile of phage’s DNA markedly differs from profiles of other serogroup B transducing S. aureus bacteriophages. DNA sequencing followed by in silico analysis explored the genome length of 43 kb and the presence of 70 ORF. By searching for homologies with other phages, we found out that the phage is very similar to phage NM4 present in the S. aureus Newman strain. Since both phages can be found as prophages in naturally occuring MRSA strains, they may serve as efficient vectors for the spread of antibiotic resistance and virulence genes in populations of staphylococci.
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