Related Experiment Video

Updated: Oct 9, 2026

Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing
08:19

Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing

Published on: July 7, 2020

Macrolide resistance in Peptostreptococcus spp. mediated by ermTR: possible source of

M Reig1, J Galan, F Baquero

  • 1Department of Microbiology, Ramón y Cajal Hospital, National Institute of Health (INSALUD), 28034 Madrid, Spain. mreig@hrc.insalud.es

Antimicrobial Agents and Chemotherapy
|February 13, 2001
PubMed

Insights

The ermTR gene, a key factor in macrolide resistance, was found in 80% of resistant Peptostreptococcus strains. This gene may transfer between different bacterial species in the throat, contributing to antibiotic resistance spread.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Antimicrobial Resistance

Background:

  • Macrolide resistance is a growing concern in bacterial infections.
  • The ermTR gene is frequently associated with macrolide resistance in Streptococcus pyogenes.

Purpose of the Study:

  • To investigate the prevalence of the ermTR gene in macrolide-resistant Peptostreptococcus strains.
  • To explore the potential for ermTR gene transfer among oropharyngeal bacteria.

Main Methods:

  • Analysis of 26 Peptostreptococcus strains for macrolide resistance.
  • Detection of the ermTR gene in resistant strains.
  • Gene transfer experiments from Peptostreptococcus magnus to Streptococcus pyogenes.

Main Results:

  • Eighty percent (21 of 26) of macrolide-resistant Peptostreptococcus strains harbored the ermTR gene.
  • The ermTR gene was confirmed as a significant macrolide resistance determinant in Peptostreptococcus.
  • Successful transfer of the ermTR gene to susceptible Streptococcus pyogenes was demonstrated.

Conclusions:

  • The ermTR gene is prevalent in macrolide-resistant Peptostreptococcus.
  • This resistance gene has the potential to circulate among diverse gram-positive bacteria in the oropharynx.
  • Understanding gene transfer mechanisms is crucial for combating antibiotic resistance.

Related Concept Videos

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...
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...
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
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...
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...
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...