Related Experiment Video

Updated: Aug 17, 2026

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
09:00

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance

Published on: May 2, 2018

Development of resistance to beta-lactam antibiotics with special reference to third-generation cephalosporins

E Collatz, L Gutmann, R Williamson

    The Journal of Antimicrobial Chemotherapy
    |September 1, 1984
    PubMed

    Insights

    Mechanisms of bacterial resistance to cephalosporins involve outer membrane changes, beta-lactamase production, and altered penicillin-binding proteins. Resistance rates in Parisian hospitals were low for Enterobacteriaceae but higher for Pseudomonas species.

    Area of Science:

    • Microbiology
    • Pharmacology
    • Infectious Diseases

    Background:

    • Beta-lactam antibiotics, including third-generation cephalosporins, are crucial for treating bacterial infections.
    • Bacterial resistance to antibiotics poses a significant public health threat.
    • Understanding resistance mechanisms is vital for effective antimicrobial therapy.

    Purpose of the Study:

    • To review the mechanisms of bacterial resistance to third-generation cephalosporins.
    • To outline the prevalence of specific resistance mechanisms in Gram-negative and Gram-positive bacteria.
    • To report the frequency of resistance in clinical settings.

    Main Methods:

    • Literature review of resistance mechanisms: outer membrane permeability, beta-lactamase production, and penicillin-binding protein (PBP) alterations.
    • Analysis of resistance prevalence related to specific bacterial types (Gram-negative vs. Gram-positive).
    • Data compilation on resistance frequency in two Parisian hospitals in 1983.

    Main Results:

    • Resistance mechanisms include changes in outer membrane permeability, beta-lactamase production, and PBP modification.
    • Gram-negative bacteria often exhibit resistance via membrane permeability and chromosome-mediated beta-lactamases.
    • Gram-positive bacteria commonly show PBP-related resistance.
    • In 1983 Parisian hospitals, overall resistance to third-generation cephalosporins was under 2% in Enterobacteriaceae but approached 15% in Pseudomonas species.

    Conclusions:

    • Outer membrane permeability, beta-lactamase activity, and PBP alterations are key cephalosporin resistance mechanisms.
    • Prevalence of these mechanisms differs between Gram-negative and Gram-positive bacteria.
    • Clinical resistance rates, exemplified by Pseudomonas, highlight the need for ongoing surveillance.

    More Related Videos

    Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing08:19

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

    Published on: July 7, 2020

    Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations11:15

    Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations

    Published on: July 24, 2021

    Related Concept Videos

    Antibiotic Selection00:57

    Antibiotic Selection

    Overview
    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...
    Production of Antibiotics01:27

    Production of Antibiotics

    Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
    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...
    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...
    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...