Related Experiment Video

Updated: Aug 16, 2026

A Platform of Anti-biofilm Assays Suited to the Exploration of Natural Compound Libraries
09:39

A Platform of Anti-biofilm Assays Suited to the Exploration of Natural Compound Libraries

Published on: December 27, 2016

The effect of penicillin on bacterial interference in vivo

E Grahn, S E Holm

    Scandinavian Journal of Infectious Diseases
    |January 1, 1987
    PubMed

    Insights

    Penicillin demonstrated a synergistic effect against beta-streptococci when alfa-streptococci were present, enhancing bacterial killing. This antibiotic interaction was observed in vivo, highlighting potential therapeutic strategies.

    Area of Science:

    • Microbiology
    • Pharmacology
    • Infectious Diseases

    Background:

    • Investigating the in vivo interference between alfa-streptococci and group A streptococci.
    • Understanding the impact of penicillin on streptococcal interactions within a host environment.

    Purpose of the Study:

    • To analyze the effect of penicillin on the in vivo interference between alfa-streptococci and group A streptococci.
    • To evaluate the synergistic or antagonistic effects of penicillin in the presence of competing streptococcal species.

    Main Methods:

    • Subcutaneous implantation of tissue cages in 9 rabbits.
    • Inoculation with alfa-streptococci and group A (beta) streptococci, both individually and in combination.
    • Administration of varying penicillin concentrations and assessment of bacterial recovery and growth inhibition at 96 hours.

    Main Results:

    • Both streptococcal species were recovered after 96 hours in untreated rabbits.
    • Alfa-streptococci maintained their in vitro growth-inhibiting capacity against beta-streptococci in vivo.
    • Penicillin showed a faster killing rate of beta-streptococci at low concentrations when alfa-streptococci were present, indicating a synergistic effect, unlike higher concentrations used alone.

    Conclusions:

    • Alfa-streptococci can inhibit group A streptococci in vivo.
    • Penicillin exhibits a synergistic effect with alfa-streptococci, leading to enhanced killing of group A streptococci.
    • This interaction suggests potential for novel therapeutic strategies involving microbial interference and antibiotics.

    More Related Videos

    In Vivo Mouse Model of Spinal Implant Infection08:03

    In Vivo Mouse Model of Spinal Implant Infection

    Published on: June 23, 2020

    Antibiotic Efficacy Testing in an Ex vivo Model of Pseudomonas aeruginosa and Staphylococcus aureus Biofilms in the Cystic Fibrosis Lung09:26

    Antibiotic Efficacy Testing in an Ex vivo Model of Pseudomonas aeruginosa and Staphylococcus aureus Biofilms in the Cystic Fibrosis Lung

    Published on: January 22, 2021

    Related Concept Videos

    Antimicrobial Effectiveness01:28

    Antimicrobial Effectiveness

    The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
    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...
    Inhibitors of Bacterial Protein Synthesis01:25

    Inhibitors of Bacterial Protein Synthesis

    Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...