Related Experiment Video

Updated: Oct 29, 2025

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

8.7K

Tracking bacterial effector protein delivery into host cells

Timothy L Cover1,2,3

  • 1Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.

Molecular Microbiology
|July 12, 2021
PubMed

Insights

Researchers developed a split luciferase assay to track Helicobacter pylori Cag T4SS-mediated CagA protein delivery into gastric cells. This method enables real-time monitoring of CagA translocation, aiding cancer pathogenesis research.

Area of Science:

  • Microbiology
  • Cell Biology
  • Cancer Research

Background:

  • Bacterial Type IV secretion systems (T4SSs) are crucial for delivering effector proteins into host cells.
  • The Helicobacter pylori Cag T4SS plays a significant role in gastric cancer pathogenesis by delivering the CagA effector protein.
  • Understanding CagA delivery mechanisms is vital for cancer research but has been limited by the lack of effective monitoring tools.

Purpose of the Study:

  • To develop and validate a novel split luciferase assay for monitoring T4SS-mediated translocation of CagA into host cells.
  • To facilitate real-time quantification and kinetic analysis of CagA delivery.
  • To investigate the role of protein unfolding in CagA secretion via the Cag T4SS.

Main Methods:

  • Development of a split luciferase reporter system to monitor CagA translocation.
  • Real-time assays to quantify CagA delivery into gastric cells.
  • Tracking of CagA fusion proteins to assess secretion requirements.

Main Results:

  • The split luciferase assay successfully monitored T4SS-mediated CagA translocation in real-time.
  • The assay allowed for the quantification of CagA delivery kinetics.
  • Protein unfolding was confirmed as important for secretion by the Cag T4SS.

Conclusions:

  • A split luciferase system provides a robust method for studying T4SS-mediated protein delivery.
  • This assay facilitates the analysis of bacterial effector protein secretion and translocation mechanisms.
  • The findings enhance our understanding of H. pylori pathogenesis and gastric cancer development.
Keywords:
bacterial secretion systemseffector proteinsmacromolecular protein complexesprotein translocation

More Related Videos

Applying Fluorescence Resonance Energy Transfer FRET to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing10:29

Applying Fluorescence Resonance Energy Transfer FRET to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing

Published on: July 6, 2016

10.9K
Split Green Fluorescent Protein System to Visualize Effectors Delivered from Bacteria During Infection07:25

Split Green Fluorescent Protein System to Visualize Effectors Delivered from Bacteria During Infection

Published on: May 24, 2018

10.7K

Related Concept Videos

Bacterial Translocation and Protein Secretion01:26

Bacterial Translocation and Protein Secretion

Bacterial protein secretion involves translocation systems to ensure proteins reach their designated locations, including the plasma membrane, periplasm, outer membrane, or the external environment. These translocation systems are vital for bacterial physiology, supporting processes like membrane assembly, enzymatic activity in the periplasm, and interactions with the external environment. The division of labor between Sec and Tat pathways ensures efficiency in handling proteins with diverse...
195
Gram-negative Bacterial Protein Secretion Systems01:17

Gram-negative Bacterial Protein Secretion Systems

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):...
281
Intracellular Movement of Viruses and Bacteria01:10

Intracellular Movement of Viruses and Bacteria

Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.0K
Receptor-mediated Endocytosis01:20

Receptor-mediated Endocytosis

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...
6.9K
Viral Replication: Lytic Cycle01:20

Viral Replication: Lytic Cycle

Bacteriophages, or phages, are viruses that specifically infect bacteria. Among them, T-even bacteriophages, such as T4, exhibit a well-characterized lytic replication cycle in Escherichia coli (E. coli). This process ensures the rapid proliferation of the virus while ultimately leading to the destruction of the bacterial host.Attachment and DNA InjectionThe infection process begins with the recognition and binding of the T4 phage to the E. coli cell surface. Tail fibers of the phage...
574
Chemotaxis in E. coli01:27

Chemotaxis in E. coli

Chemotaxis in Escherichia coli is a sensory-driven motility mechanism that enables bacteria to navigate chemical gradients, moving toward beneficial environments while avoiding harmful conditions. This process relies on a signal transduction system integrating external chemical cues with flagellar motor control.Chemoreceptors and Signal DetectionE. coli detects chemical gradients through methyl-accepting chemotaxis proteins (MCPs), which are membrane-bound chemoreceptors that sense attractants...
286