This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Takác, M. Articles by Bläsi, U. Search for Related Content PubMed PubMed Citation Articles by Takác, M. Articles by Bläsi, U.

Phage P68 Virion-Associated Protein 17 Displays Activity against Clinical Isolates of Staphylococcus aureus

Marian Taká and Udo Bläsi^*

Max F. Perutz Laboratories, Department of Microbiology and Immunobiology, University Departments at the Vienna Biocenter, Dr. Bohrgasse 9/4, 1030 Vienna, Austria

Received 27 July 2004/ Returned for modification 26 January 2005/ Accepted 27 March 2005

Phage-encoded murein hydrolases are either part of the lysis cassette or found as structural components of the phage virion. Here, we show that Staphylococcus aureus bacteriophage P68 contains a virion-associated muralytic enzyme. Protein 17 has a composite structure. The N-terminal part comprises the muralytic activity, whereas the C-terminal part is required for binding to the cell surface. A high multiplicity of infection with phage P68 caused rapid lysis, and purified protein 17 triggered premature lysis when added to S. aureus cells prior to infection with P68, suggesting that it functions to weaken the murein at the site of phage DNA entry. Protein 17 displayed activity against clinical S. aureus isolates, which are resistant to infection by phage P68, demonstrating that the protein targets surface structures distinct from the phage receptor. This broad activity spectrum of protein 17 could qualify virion-associated muralytic enzymes as attractive antimicrobials.