Related Experiment Video

Updated: Aug 13, 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

Further studies on microbiological ring-expansion of penicillin N

Y Sawada, N A Hunt, A L Demain

    The Journal of Antibiotics
    |December 1, 1979
    PubMed

    Insights

    Researchers enhanced the microbiological ring-expansion of penicillin N to deacetoxycephalosporin C by 70-fold. Optimized conditions include specific iron sulfate and ascorbate concentrations, pH, and temperature for improved antibiotic precursor production.

    Area of Science:

    • Biochemistry
    • Microbiology
    • Biotechnology

    Background:

    • Cephalosporin C is a key antibiotic precursor.
    • Efficient conversion of penicillin N to deacetoxycephalosporin C is crucial for biosynthesis.
    • Previous methods for in vitro ring-expansion were suboptimal.

    Purpose of the Study:

    • To significantly enhance the rate of microbiological ring-expansion of penicillin N to deacetoxycephalosporin C.
    • To optimize reaction conditions for improved yield and efficiency.

    Main Methods:

    • Utilized protoplast lysates of the antibiotic-negative mutant Cephalosporium acremonium M-0198.
    • Systematically varied concentrations of iron sulfate (FeSO4) and ascorbate.
    • Determined optimal pH, temperature, and substrate (penicillin N) concentration.
    • Assessed the effects of various other ions and cofactors.

    Main Results:

    • Achieved a 70-fold increase in the ring-expansion rate compared to earlier systems.
    • Identified optimal FeSO4 (0.04 mM) and ascorbate (0.67 mM) concentrations.
    • Established optimal reaction conditions at pH 7.2 and 25°C.
    • Found that specific ring-expansion activity peaked 13 hours post-growth cessation.

    Conclusions:

    • The optimized in vitro system dramatically improves penicillin N to deacetoxycephalosporin C conversion.
    • Specific inorganic ions and reaction parameters are critical for maximizing enzymatic activity.
    • This enhanced method offers a more efficient route for producing key cephalosporin intermediates.

    More Related Videos

    A Novel Method to Determine the Longitudinal Antibacterial Activity of Drug-Eluting Materials06:18

    A Novel Method to Determine the Longitudinal Antibacterial Activity of Drug-Eluting Materials

    Published on: March 3, 2023

    Super-resolution Imaging of Proteus mirabilis Biofilm by Expansion Microscopy07:10

    Super-resolution Imaging of Proteus mirabilis Biofilm by Expansion Microscopy

    Published on: July 18, 2025

    Related Concept Videos

    History of Microbiology01:28

    History of Microbiology

    Microbiology, a scientific field dedicated to the study of microorganisms, has undergone profound development since its inception in the 17th century. Its history is marked by key discoveries and technological advancements that have shaped our understanding of life at the microscopic level and transformed medicine, agriculture, and industry.Early Foundations of MicrobiologyThe early foundations of microbiology were built on groundbreaking observations and the development of pioneering...
    Special Staining Techniques01:13

    Special Staining Techniques

    Specialized staining techniques play a vital role in microbiology by enabling the visualization of specific bacterial structures that remain undetectable with standard microscopy methods. These techniques not only enhance the structural visualization of bacterial cells but also provide critical insights into their pathogenicity and classification. Additionally, they support diagnostic and research endeavors in microbiology by identifying key bacterial features.Capsule Staining for Virulence...
    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...