Related Experiment Video

Updated: May 12, 2026

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Novel bacteriophage lysin with broad lytic activity protects against mixed infection by Streptococcus pyogenes and

Daniel B Gilmer1, Jonathan E Schmitz, Chad W Euler

  • 1Laboratory of Bacterial Pathogenesis and Immunology, The Rockefeller University, New York, New York, USA.

Antimicrobial Agents and Chemotherapy
|April 11, 2013
PubMed

Insights

A novel bacteriophage lysin, PlySs2, demonstrates broad-spectrum activity against dangerous Gram-positive pathogens like MRSA and Streptococcus pyogenes. This stable and effective therapeutic shows promise in combating antibiotic resistance.

Area of Science:

  • Microbiology
  • Biochemistry
  • Therapeutics

Background:

  • Antibiotic resistance in Gram-positive pathogens like Methicillin-resistant Staphylococcus aureus (MRSA) and Streptococcus pyogenes (group A Streptococcus [GrAS]) necessitates novel therapeutic strategies.
  • The emergence of resistance to existing antibiotics poses a significant threat to public health, driving the search for alternative treatments.

Purpose of the Study:

  • To identify and characterize a novel bacteriophage lysin with broad lytic activity against clinically significant Gram-positive bacteria.
  • To evaluate the stability, efficacy, and resistance potential of the identified lysin, PlySs2, as a potential therapeutic agent.

Main Methods:

  • Identification and purification of the bacteriophage lysin PlySs2 from Streptococcus suis.
  • Assessment of PlySs2's lytic activity spectrum against various Gram-positive pathogens, including MRSA and S. pyogenes.
  • Evaluation of PlySs2's stability under different temperature and storage conditions.
  • In vitro and in vivo efficacy studies using bacteremia models and MIC determination.
  • Analysis of resistance development to PlySs2 compared to mupirocin.

Main Results:

  • PlySs2 exhibited broad lytic activity against a wide range of Gram-positive bacteria, including MRSA, vancomycin-intermediate S. aureus (VISA), S. pyogenes, and Listeria species.
  • The lysin demonstrated remarkable stability at various temperatures and after multiple freeze-thaw cycles.
  • In vitro, PlySs2 significantly reduced MRSA and S. pyogenes growth and showed a low minimum inhibitory concentration (MIC) for MRSA.
  • A single dose of PlySs2 provided significant protection in a murine bacteremia model.
  • No resistance developed to PlySs2 upon serial exposure, unlike mupirocin.

Conclusions:

  • PlySs2 is a potent, stable, and broad-spectrum bacteriophage lysin with significant therapeutic potential against critical Gram-positive pathogens.
  • Its ability to overcome existing resistance mechanisms and lack of induced resistance make PlySs2 a promising candidate for novel antibiotic therapies.

More Related Videos

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds06:36

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds

Published on: September 8, 2021

Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics09:23

Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics

Published on: January 5, 2024

Related Concept Videos

Lytic Cycle of Bacteriophages01:30

Lytic Cycle of Bacteriophages

Bacteriophages, also known as phages, are specialized viruses that infect bacteria. A key characteristic of phages is their distinctive “head-tail” morphology. A phage begins the infection process (i.e., lytic cycle) by attaching to the outside of a bacterial cell. Attachment is accomplished via proteins in the phage tail that bind to specific receptor proteins on the outer surface of the bacterium. The tail injects the phage’s DNA genome into the bacterial cytoplasm. In the lytic replication...
Lysogenic Cycle of Bacteriophages00:43

Lysogenic Cycle of Bacteriophages

In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Viral Replication: Lysogenic Cycle01:16

Viral Replication: Lysogenic Cycle

The lysogenic cycle is a crucial viral replication strategy that allows bacteriophages to persist within host cells without immediately destroying them. This process is primarily observed in temperate phages, such as bacteriophage lambda (λ), which infects Escherichia coli. The cycle allows the viral genome to persist across bacterial generations while keeping host cells viable.Integration of the Viral GenomeUpon infection, bacteriophage lambda attaches to the bacterial surface and injects its...
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...