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Updated: Oct 16, 2026

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
08:58

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes

Published on: March 3, 2023

[Drug-resistant bacteria of current topics and their resistance mechanisms--PRSP and BLNAR]

K Ubukata

    Rinsho Byori. the Japanese Journal of Clinical Pathology
    |May 11, 2000
    PubMed

    Insights

    Antibiotic resistance is rising in Streptococcus pneumoniae and Haemophilus influenzae due to altered penicillin-binding proteins (PBPs). This impacts treatment effectiveness, particularly for beta-lactam antibiotics.

    Area of Science:

    • Microbiology
    • Molecular Biology
    • Infectious Diseases

    Background:

    • Increasing prevalence of beta-lactam antibiotic resistance in Streptococcus pneumoniae and Haemophilus influenzae.
    • Identification of resistant strains as penicillin-resistant S. pneumoniae (PRSP) and beta-lactamase-negative ampicillin-resistant H. influenzae (BLNAR).

    Purpose of the Study:

    • To investigate the molecular mechanisms of beta-lactam resistance in PRSP and BLNAR.
    • To identify specific alterations in penicillin-binding proteins (PBPs) responsible for resistance.

    Main Methods:

    • Analysis of genetic mutations in genes encoding PBPs in resistant bacterial isolates.
    • Comparison of PBP alterations between PRSP and BLNAR strains.

    Main Results:

    • Penicillin-resistant S. pneumoniae (PRSP) showed alterations in pbp1a, pbp2x, and pbp2b genes, affecting PBP1A, -2X, and -2B.
    • Beta-lactamase-negative ampicillin-resistant H. influenzae (BLNAR) exhibited mutations exclusively in the ftsI gene, encoding PBP3A.
    • PBP alterations result in low-level antibiotic resistance, diminishing the bactericidal effect of beta-lactams.

    Conclusions:

    • Distinct PBP alteration mechanisms drive beta-lactam resistance in S. pneumoniae and H. influenzae.
    • Understanding these mechanisms is crucial for developing effective antimicrobial strategies against resistant bacterial infections.

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