Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Bacterial Gastroenteritis01:18

Bacterial Gastroenteritis

41
Bacterial gastroenteritis, characterized by diarrhea, abdominal cramps, and vomiting, is often caused by ingestion of contaminated food or water and is frequently associated with pathogenic Escherichia coli strains. These microbes exploit two principal mechanisms to inflict disease.Shiga toxin–producing E. coli, also referred to as STEC—notably O157:H7—release Shiga toxins that target ribosomes, blocking protein synthesis. The B subunit of the toxin binds the host glycolipid...
41
Bacterial Toxins01:12

Bacterial Toxins

51
Bacterial toxins are sophisticated virulence factors that enable pathogenic bacteria to interact with, invade, and damage host tissues. These toxins fall broadly into two types: protein exotoxins, which are secreted into the environment and target specific host receptors, and lipopolysaccharide endotoxins, which are structural components of the bacterial outer membrane released primarily during bacterial lysis or membrane shedding. Exotoxins generally act more selectively, binding to cell...
51
Gram-negative Bacterial Protein Secretion Systems01:17

Gram-negative Bacterial Protein Secretion Systems

1.5K
Gram-negative bacteria utilize sophisticated protein secretion systems to transport proteins across their double-membrane envelope into the extracellular environment or host cells. Based on their mechanism of action, these systems are classified into one-step and two-step pathways.One-Step Secretion Systems (Types I, III, IV, and VI)One-step secretion systems bypass the periplasm entirely, forming a continuous channel that spans both the inner and outer membranes:Type I Secretion System (T1SS):...
1.5K
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

36
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
36
Receptor-mediated Endocytosis01:20

Receptor-mediated Endocytosis

11.9K
Receptor-mediated endocytosis is when bulk amounts of specific molecules are imported into a cell after binding to cell surface receptors. The molecules bound to these receptors are taken into the cell through inward folding of the cell surface membrane, which is eventually pinched off into a vesicle within the cell. Structural proteins, such as clathrin, coat the budding vesicle.
Clathrin-Mediated Endocytosis of LDL
One well-characterized example of receptor-mediated endocytosis is the...
11.9K
Stringent Response in E. coli01:23

Stringent Response in E. coli

468
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
468

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

After Verification: Analysis of Kim and Ko's Response to M. Jobling (Re: Trust But Verify; DOI: 10.1089/mdr.2018.0426).

Microbial drug resistance (Larchmont, N.Y.)·2022
Same author

The Retraction of a Plasmid-Phage Chimera Genome Assembly Study Leaves Serious Issues Unaddressed-Essentially, Nolo Contendere.

Antimicrobial agents and chemotherapy·2022
Same author

Lysogeny of Escherichia coli by the Obligately Lytic Bacteriophage T1: Not Proven.

mBio·2021
Same author

Escherichia coli prophage sequences are not present in a carbapenemase plasmid from Klebsiella. Reply to Authors' response to Letter to the Editor: If extraordinary data are not first corroborated, we risk being led astray: Occam's razor does not support the existence of plasmid-prophage chimeras. Comment on 'Effects of cryptic prophage regions in a plasmid carrying a carbapenemase gene on survival against antibiotic stress'.

International journal of antimicrobial agents·2021
Same author

Novel Type II Heat-Labile Enterotoxin Produced by Human Disease Outbreak Isolates of <i>Escherichia coli</i> Is a Member of the LT-IIa Family and Should Not Form a New Group: Clarification of Nomenclature and Precedent.

Open forum infectious diseases·2020
Same author

Evaluation of the Immunogenicity and Protective Efficacy of an Enterotoxigenic Escherichia coli CFA/I Adhesin-Heat-Labile Toxin Chimera.

Infection and immunity·2020
Same journal

A history of <i>EcoSal Plus</i>.

EcoSal Plus·2025
Same journal

Transcriptional reprogramming by bacteriophage T4: turning the host transcriptional machinery to the dark side.

EcoSal Plus·2025
Same journal

Bacteriophage T4 genome packaging: mechanism and application.

EcoSal Plus·2025
Same journal

The bacteriophage T4 homologous recombination system: mechanism, applications, conservation, and environmental significance.

EcoSal Plus·2025
Same journal

The bacteriophage T4 replisome: a model system for understanding DNA replication mechanisms.

EcoSal Plus·2025
Same journal

Biology of host-dependent restriction-modification in prokaryotes.

EcoSal Plus·2025
See all related articles

Related Experiment Video

Updated: Apr 1, 2026

Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
10:41

Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance

Published on: January 3, 2012

13.9K

Heat-Labile Enterotoxins.

Michael G Jobling, Randall K Holmes

    Ecosal Plus
    |October 8, 2015
    PubMed
    Summary
    This summary is machine-generated.

    Heat-labile enterotoxins (LTs) from E. coli are similar to cholera toxin (CT). Research highlights their structural similarities and critical amino acid residues for enzymatic activity, crucial for understanding cholera-like diseases.

    More Related Videos

    Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions
    12:23

    Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions

    Published on: October 13, 2015

    9.0K
    Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
    07:58

    Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates

    Published on: May 30, 2017

    11.6K

    Related Experiment Videos

    Last Updated: Apr 1, 2026

    Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
    10:41

    Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance

    Published on: January 3, 2012

    13.9K
    Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions
    12:23

    Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions

    Published on: October 13, 2015

    9.0K
    Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
    07:58

    Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates

    Published on: May 30, 2017

    11.6K

    Area of Science:

    • Microbiology
    • Molecular Biology
    • Toxicology

    Background:

    • Heat-labile enterotoxins (LTs) from Escherichia coli are structurally related to cholera toxin (CT).
    • These toxins, along with others, form the Vibrio cholerae-E. coli family of LTs.
    • Enterotoxigenic E. coli (ETEC) strains produce LTs causing cholera-like illness.

    Purpose of the Study:

    • To investigate the structural and functional similarities between LTs and CT.
    • To identify key residues in the LT A subunit critical for enzymatic activity.
    • To understand the mechanism of holotoxin entry into target cell cytosol.

    Main Methods:

    • X-ray crystallography was used to determine the 3D structures of CT, LTpI, and LTIIb.
    • Site-directed mutagenesis was employed to identify critical residues in the A subunits.
    • Analysis of gene location (plasmids, chromosomes, phage) for LTI genes (elt).

    Main Results:

    • The three-dimensional crystal structures of CT, LTpI, and LTIIb are highly similar.
    • Specific residues (His44, Val53, Ser63, Val97, Glu110, Glu112) in the A subunits are critical for structure and enzymatic activity.
    • The A1 fragment must access the cytosol for enzymatic activity, requiring holotoxin entry.

    Conclusions:

    • LTs and CT share significant structural homology, indicating a common evolutionary origin.
    • Understanding critical residues provides insights into toxin mechanisms and potential therapeutic targets.
    • The mechanism of holotoxin translocation into the cytosol is essential for enterotoxin function.