Genome sequence of a serotype M28 strain of group a streptococcus: potential new insights into puerperal sepsis and

Related Experiment Video

Updated: Aug 16, 2026

A Murine Model of Group B Streptococcus Vaginal Colonization
10:19

A Murine Model of Group B Streptococcus Vaginal Colonization

Published on: November 16, 2016

Nicole M Green1, Shizhen Zhang, Stephen F Porcella

  • 1Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, USA.

The Journal of Infectious Diseases
|August 10, 2005
PubMed

Insights

Group A Streptococcus serotype M28 strains, linked to puerperal sepsis, possess unique foreign genes. These genes encode proteins expressed during infection, contributing to the pathogen

Area of Science:

  • Microbiology
  • Genomics
  • Infectious Diseases

Background:

  • Puerperal sepsis was a leading cause of mortality in 19th-century Europe.
  • Group A Streptococcus, particularly serotype M28, is a significant pathogen in puerperal sepsis.
  • Understanding the genetic basis of M28 strain virulence is crucial for combating infections.

Purpose of the Study:

  • To investigate the genomic basis for the prevalence of group A Streptococcus serotype M28 in puerperal sepsis.
  • To identify novel virulence factors and host-pathogen interaction molecules in M28 strains.

Main Methods:

  • Whole-genome sequencing of a representative group A Streptococcus serotype M28 strain.
  • Bioinformatic analysis to identify virulence factors and foreign DNA elements.
  • Analysis of gene expression and protein localization.

Main Results:

  • The sequenced M28 strain genome contains genes for prophage virulence factors and cell-surface proteins.
  • A 37.4-kb foreign DNA element, shared with group B Streptococcus, encodes 7 extracellular proteins.
  • These proteins are expressed extracellularly and detected in human infections, indicating their role in pathogenesis.

Conclusions:

  • Acquisition of foreign genetic material has facilitated the evolution of group A Streptococcus serotype M28 into a specialized pathogen.
  • The identified virulence factors and expressed proteins offer potential targets for therapeutic interventions.
  • Genomic insights into M28 strains advance our understanding of puerperal sepsis and streptococcal infections.

More Related Videos

Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/4306:06

Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43

Published on: September 11, 2020

Related Concept Videos

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...
Determinants of Bacterial Pathogenicity and Virulence01:20

Determinants of Bacterial Pathogenicity and Virulence

Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...
Modern Molecular Taxonomy01:29

Modern Molecular Taxonomy

Advancements in molecular biology have revolutionized the identification and characterization of bacteria, with multiple methods leveraging DNA sequencing for enhanced precision. As sequencing technologies improve and costs decline, these approaches are increasingly used in clinical, environmental, and evolutionary studies.Multilocus Sequence Typing (MLST) examines several housekeeping genes, essential chromosomal genes encoding cellular functions, to distinguish strains. Approximately...
Streptococcal Pharyngitis01:27

Streptococcal Pharyngitis

Streptococcal pharyngitis, commonly known as “strep throat,” is an acute infection of the oropharyngeal tissues caused by the Gram‑positive Group A Streptococcus (Streptococcus pyogenes). Transmission occurs primarily through respiratory droplets expelled during coughing, sneezing, or talking.Mechanisms of Host Entry and Immune EvasionUpon entering the host, S. pyogenes adheres to the mucosal epithelial cells of the pharynx via surface proteins, notably lipoteichoic acid and the antiphagocytic...
Bacterial Meningitis II: Pathophysiology01:26

Bacterial Meningitis II: Pathophysiology

Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...