Related Experiment Video

Updated: Aug 27, 2026

Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG
12:23

Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG

Published on: May 16, 2017

Studies of the high molecular weight penicillin-binding proteins of Bacillus subtilis

G Kleppe, J L Strominger

    The Journal of Biological Chemistry
    |June 10, 1979
    PubMed

    Insights

    Researchers isolated high molecular weight penicillin-binding proteins (PBPs) from Bacillus subtilis using affinity chromatography. These distinct PBPs, likely products of separate genes, showed no detectable enzymatic activity in membrane fractions.

    Area of Science:

    • Microbiology
    • Biochemistry
    • Molecular Biology

    Background:

    • Bacillus subtilis possesses seven or eight distinct penicillin-binding proteins (PBPs) located in its cell membranes.
    • Understanding the specific roles and properties of these PBPs is crucial for deciphering bacterial cell wall synthesis and antibiotic resistance mechanisms.

    Purpose of the Study:

    • To isolate and characterize high molecular weight penicillin-binding proteins (PBPs) from Bacillus subtilis membranes.
    • To investigate the enzymatic activity and genetic origin of purified PBPs.

    Main Methods:

    • Covalent affinity chromatography utilizing cephalosporins as ligands was employed for PBP isolation.
    • Purified PBPs were analyzed for structural and physical properties, including molecular weight and peptide generation after pepsin digestion.

    Main Results:

    • Milligram quantities of three high molecular weight PBPs (PBP 1 ab, PBP 2b, and PBP 4) were successfully isolated, free from contamination by PBP 5 (D-alanine carboxypeptidase).
    • Pure PBP 2b was obtained through specific manipulation of affinity chromatography conditions.
    • Pepsin digestion yielded a single major penicilloyl peptide from each high molecular weight PBP, suggesting each is a distinct gene product.
    • No transpeptidase or D-alanine carboxypeptidase activity was detected in mixtures of the purified high molecular weight PBPs.

    Conclusions:

    • The study successfully isolated and purified key penicillin-binding proteins from Bacillus subtilis.
    • Evidence suggests that PBP 1 ab, PBP 2b, and PBP 4 are products of separate genes.
    • The purified high molecular weight PBPs did not exhibit detectable enzymatic activity under the tested conditions, warranting further investigation into their specific functions.

    More Related Videos

    Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP009208:53

    Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092

    Published on: October 2, 2017

    Adherence of Bacteria to Plant Surfaces Measured in the Laboratory07:07

    Adherence of Bacteria to Plant Surfaces Measured in the Laboratory

    Published on: June 19, 2018

    Related Concept Videos

    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...