Related Experiment Video

Updated: Aug 25, 2025

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
07:10

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

9.1K

Molecular Study of Accessory-Gene-Regulator in Staphylococcus aureus Isolated from Sepsis in Pediatric Patients

Mervat Mashaly, Asmaa Bakr, Eman A Elmansoury

    Clinical Laboratory
    |October 17, 2022
    PubMed

    Insights

    Pediatric sepsis caused by Staphylococcus aureus shows increased biofilm formation, particularly in Methicillin-resistant S. aureus (MRSA). The agr group I gene was predominant in MRSA and linked to biofilm production.

    Area of Science:

    • Microbiology
    • Infectious Diseases
    • Pediatrics

    Background:

    • Pediatric sepsis from Staphylococcus aureus presents significant morbidity and mortality.
    • The Accessory-Gene-Regulator (agr) system influences S. aureus virulence gene expression.
    • Understanding agr genotypes is crucial for pediatric sepsis management.

    Purpose of the Study:

    • Investigate the prevalence of agr genotypes in S. aureus from pediatric sepsis cases.
    • Assess the relationship between agr genotypes, biofilm formation, and antibiotic resistance.
    • Determine the role of agr in the pathogenesis of pediatric S. aureus sepsis.

    Main Methods:

    • Retrospective cross-sectional study of 131 pediatric sepsis cases due to S. aureus.
    • Biofilm formation assessed using the microplate method.
    • Antibiotic susceptibility determined by disc diffusion; agr genotypes identified via PCR.

    Main Results:

    • Methicillin-resistant S. aureus (MRSA) identified in 53.4% of isolates; 58% formed biofilms.
    • agr group I was the most prevalent genotype (41.2%), particularly in MRSA.
    • MRSA showed significantly higher biofilm formation (65.7%) and a strong association with agr I (68.6%) compared to MSSA.

    Conclusions:

    • Biofilm formation is increased in S. aureus from pediatric sepsis, with higher rates in MRSA.
    • agr group I is the predominant genotype in pediatric S. aureus sepsis isolates.
    • agr I is significantly associated with MRSA and enhanced biofilm formation in pediatric sepsis.
    Abstract

    More Related Videos

    A Tandem Liquid Chromatography–Mass Spectrometry-based Approach for Metabolite Analysis of Staphylococcus aureus08:03

    A Tandem Liquid Chromatography–Mass Spectrometry-based Approach for Metabolite Analysis of Staphylococcus aureus

    Published on: March 28, 2017

    10.2K
    Development and Assessment of Intracellular Infection Models for Staphylococcus aureus08:32

    Development and Assessment of Intracellular Infection Models for Staphylococcus aureus

    Published on: January 17, 2025

    661

    Related Concept Videos

    Gene Regulation in Microbial Communities: Quorum Sensing01:28

    Gene Regulation in Microbial Communities: Quorum Sensing

    Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
    76
    Global Regulatory Systems01:28

    Global Regulatory Systems

    Global regulatory systems in bacteria enable rapid and coordinated responses to environmental changes by integrating sensory inputs with gene expression, ensuring efficient adaptation to fluctuating conditions. Key global regulatory mechanisms include regulons, two-component systems, sigma factors, and secondary messengers.Regulons and Global RegulatorsA regulon is a collection of genes and operons controlled by a common global regulator. These regulators enable bacteria to prioritize resource...
    63