Location of the major bacteriophage elements in the chromosome of SF370.

<p>Triangles represent the location of the four main bacteriophage-like elements in the circular genome of <i>S</i>. <i>pyogenes</i> strain SF370. Numbers in triangles represent the corresponding phage elements with their size and encoded virulence factors identified in the table below. Derived from GenBank nucleotide accession number: AE004092.</p

Confirmed phage <i>attB</i> sequences in <i>S</i>. <i>pyogenes</i> SF370 prophage KO mutants.

<p>Confirmed phage <i>attB</i> sequences in <i>S</i>. <i>pyogenes</i> SF370 prophage KO mutants.</p

Secreted DNase activity of SF370SmR and CEM1ΔΦ.

<p>Both strains were cultured on the same DNase Test Agar plate with Methyl Green for 17 h. A, SF370SmR WT colonies; B, CEM1ΔΦ full phage KO. Clearing zones around the colonies resulted from hydrolysis of the DNA-methyl green substrate, and signify DNase activity.</p

Pulse field gel electrophoresis (PFGE) analysis of <i>S</i>. <i>pyogenes</i> SF370SmR and single phage deletion mutants.

<p>PFGE patterns of SmaI digested genomic DNA from A, the phage wild type (WT) strain SF370SmR and the single phage KOs CEM1Δ(1–4), and B, the quadruple full phage KO CEM1ΔΦ compared to WT strain SF370. Labeled arrows indicate DNA fragments that contain the corresponding integrated phage or phage-like elements, based on the genome sequence of SF370. A loss or drop of these DNA fragments represents a phage or SpyCIM1 deletion. Numbers at top indicate which phages have been deleted: 1, Φ370.1 (40.9kb), strain CEM1Δ1; 2, Φ370.2 (42.5 kb), strain CEM1Δ2; 3, Φ370.3 (33.5Kb), strain CEM1Δ3; 4, Φ370.4/SpyCIM1 (13.5kb), strain CEM1Δ4; (1,2,3,4), all 4 phage elements deleted to create strain CEM1ΔΦ. All lanes in A and B originated from the same PFGE gel as shown in (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146408#pone.0146408.s002" target="_blank">S2 Fig</a>). λ, Lambda ladder, New England Biolabs PFG Marker with DNA fragment sizes on adjacent to gel images.</p