Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Phage A1 morphology and growth characteristics. ( A ) TEM micrograph of purified Phage A1; ( B ) SEM micrograph of Phage A1 bound to S. pyogenes ATCC 12202 at multiplicity of infection (MOI) 25 after 10 min of coincubation; ( C ) Bacteriolytic activity of Phage A1 on S. pyogenes ATCC 12202 infected at different MOIs over time. Each curve shows mean values ± SD of one out of three experiments in triplicates; ( D ) One-step growth curves (OSGCs) of Phage A1 on S. pyogenes ATCC 12202. Mean values ± SD from three independent experiments are shown.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Purification, Infection, Activity Assay

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Phage A1 characteristics.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques:

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Genome sequence and phylogeny of S. pyogenes bacteriophage A1. ( A ) The Phage A1 genome is a 37,239 bp long circular dsDNA genome. Fifty-two gene products (Gps) were identiFigure 23. were encoding hypothetical proteins (gray). The genome follows the modular organization observed in other streptococcal phages, consisting of genes involved in regulation (brown), DNA replication (purple), nucleases (marine blue), DNA packaging (blue), portal protein (turquoise), capsid structure (dark green), tail morphogenesis (light green), holins (yellow) and a lysin (orange); ( B ) Whole genome-based phylogenetic tree of Phage A1 among streptococcal phages. The branch lengths are scaled in terms of the GBDP distance formula D 0 . Branch support was inferred from 100 pseudo-bootstrap replicates each.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Sequencing

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Phage A1 genome annotation.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Scaffolding

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Phage A1 is likely a temperate phage, and Phage A1 survivors become resistant to subsequent infections. ( A , top) Genomic DNA was screened by PCR for phage integration with primers specific to Phage A1 (F + R1) and primers that should not amplify an amplicon if the Phage DNA is integrated into the genome of S. pyogenes (F + R2) (F: forward, R: reverse); (A, bottom) Agarose gel showing PCR amplicons of both combinations F + R1 (up) and F + R2 (down) in S. pyogenes ATCC 12202. A1: Phage A1 genome, WT: wild type S. pyogenes ATCC 12202, S1: phage survivor 1, Scheme 2. phage survivor 2 and S3: phage survivor 3; ( B ) Representative pictures of S. pyogenes ATCC 12202 and SF370, and their phage-surviving strains after 4 h of infection at MOIs 0.1, 1, 10 and 100 compared to uninfected growth (MOI 0). Each image represents WT strains and one out of three phage-surviving clones that were infected in biological triplicates.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Amplification, Agarose Gel Electrophoresis, Infection, Clone Assay

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Phage A1-surviving strains do not influence host immune responses or antibiotic tolerance compared to wild type. ( A ) Overnight cytokine production by BLaER1 cells after infection with WT S. pyogenes SF370 and phage-surviving strains. ( B ) The percentage of BLaER1 cell death after infection with Phage A1 survivors or WT S. pyogenes SF370 is shown. ( A , B ) Mock: buffer control, S1: phage survivor 1, S2: phage survivor 2 and S3: phage survivor 3; ( C ) Ampicillin susceptibility profiles of S. pyogenes SF370 and survivor strains are shown. S1: phage survivor 1, S2: phage survivor 2 and S3: phage survivor 3; (A–C) Pooled data from three or four independent experiments are shown. Statistical significance between groups was determined by one-way ANOVA tests.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Infection, Control

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: Impaired capsule-based phage resistance results in more detectable CRISPR-Cas-mediated spacer acquisition. ( A ) Lysis profiles of Phage A1 on S. pyogenes SF370, ISS3348, and their isogenic ΔhasA strains. Each curve shows mean values ± SD of one out of three experiments in triplicates; ( B ) Phage A1 efficiency of plaquing (EOP) on various M1 serotype S. pyogenes , and their isogenic ΔhasA or CovS mutant strain; ( C ) Phage A1 EOP on S. pyogenes ISS3348 and ISS3348 ΔhasA grown in the absence or presence of hyaluronidase (H + ); ( B , C ) Results are presented as mean values ± SD from three independent experiments. p < 0.05 determined by paired t tests was considered statistically significant. * p < 0.05, ** p < 0.01, NS = not significant; ( D ) Representative agarose gels showing amplified CRISPR arrays of WT S. pyogenes SF370 (up), SF370 ΔhasA (down), and 9 surviving colonies (1–9) for both strains after Phage A1 infection.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: CRISPR, Lysis, Mutagenesis, Amplification, Infection

Journal: Viruses

Article Title: Survival Strategies of Streptococcus pyogenes in Response to Phage Infection

doi: 10.3390/v13040612

Figure Lengend Snippet: S. pyogenes -derived membrane vesicles inhibit phage infection. ( A ) Representative SEM micrographs of S. pyogenes SF370-infected with Phage A1 at MOI 10 are shown after 5, 15, 25, 45, 60 and 90 min of coincubation; ( B ) Growth curves of WT SF370 after Phage A1 infection that was either pre-incubated with membrane vesicles (MVs) or left untreated. Phage: S. pyogenes :MV ratio of 1:1:1000 is shown. Mean values ± SD from one out of three independent experiments in . bound to a S. pyogenes SF370-derived MV; ( D ) TEM micrograph of a S. pyogenes ISS3348-derived MV bound to Phage A1; ( C , D ) Representative images are shown for at least three sample preparations.

Article Snippet: Phage A1 (ATCC 12202-B1) was added to achieve a final multiplicity of infection (MOI) of 0.1.

Techniques: Derivative Assay, Membrane, Infection, Incubation