Recommended Name ?lysin PlyGBS
Systematic Name ?peptidoglycan N-acetylmuramoylhydrolase
Alternative Name ?endolysin PlyGBS
GBS bacteriophage lysin
mucopeptide glucohydrolase
mucopeptide N-acetylmuramoylhydrolase
peptidoglycan N-acetylmuramoylhydrolase
Uniprot IDQ5MY96
General Mode of ActionEnzymatic cleavage of peptidoglycan which results in a rapid lysis of the bacterial cell.
phiBIOTICS Family ?Lysozyme
Reaction ?1. Catalysis of the hydrolysis of the beta-(1->4) linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrins
    Corresponding Pfam domain: Glyco_hydro_25
    Evidence: experimental (PubMed: 11259652)
2. Catalysis of the hydrolysis of the bonds in cell wall peptidoglycans (amidohydrolase/peptidase activity)
    EC: n/a
    Corresponding Pfam domain: CHAP
    Evidence: predicted
Source Organism ?Streptococcus phage NCTC11261
Target Organism ?Streptococcus agalactiae
Streptococcus pyogenes
Note on TargetS. pyogenes is also known as Group A Streptococcus.S. agalactiae is also known as Group B Streptococcus.PlyGBS also target Group C, G and L streptococci.
Disease ?Acute glomerulonephritis (Group A Streptococcus)
Acute rheumatic fever (Group A Streptococcus)
Impetigo (Group A Streptococcus)
Infective endocarditis (Group A Streptococcus)
Neonatal sepsis (Group B Streptococcus)
Pharyngitis (Group A Streptococcus)
Postpartum infections (Group B Streptococcus)
Rheumatic heart disease (Group A Streptococcus)
Scarlet fever (Group A Streptococcus)
State ?Tested
Reference ?11259652

Studies found: 2

Antimicrobial Agent
Study Type
Relevant ResultsAdverse Effects and Other IssuesReference ?
PlyGBS in vitro
  • 8 GBS strains
    (each of which represented distinct serotype) and all are human clinical isolates
  • streptococcal strains belonging to different Lancefield groups: A,C,G,L,D,E,N
  • non-Lancefield oral streptococcal strains:
    Streptococcus gordonii
    Streptococcus oralis
    Streptococcus salivarius
    Streptococcus sobrinus
    Streptococcus mutans
  • nonstreptococcal Gram-positive bacterial strains:
    Bacillus cereus
    Staphylococcus aureus
  • vaginal commensal bacterial strains:
    Lactobacillus acidophilus
    Lactobacillus crispatus
Efficient lytic activity against all strains tested. Within 1 h 40 U of PlyGBS lysed NCTC11237 IIIR strain decreasing viable titers by 2 log10 CFU/mL. Other GBS strains shown variation due to presence of different structure between capsules.

Significant lytic activity against A,C,G,L group streptococci.

Medium to low lytic activity against S. salivarius, S. gordonii, and S. mutans.

No lytic activity was observed with B. cereus, S. aureus or vaginal commensal bacteria L. acidophilus and L. crispatus.
PlyGBS in vivo
  • murine model of vaginal and upper respiratory GBS colonization



Single dose of PlyGBS (10 U; n=15) administered 24 h after inoculation with 10x6 CFU of streptomycin-resistant GBS NCTC 11237 cells resulted in approximately 3 log decrease in the viable titer, lysin were effective vaginally in mice up to 4 h post-treatment.
Single dose of PlyGBS lysin (10 U; n=20) resulted in sufficient elimination of bacterial colonization of the mice oropharynx mucosa (mice were challenged with 10x8 CFU of streptomycin-resistant GBS NCTC 11237 cells).
Other Issues
Lysin optimal pH was found to be about pH 5.0, is within the range of normally found in human vaginal tract asumming that effectivness demonstrated in mouse model will translate eficiently to the human vagina, more investigation is required to confirm this.