Related Experiment Video

Updated: Jul 15, 2026

Preparation of Mycobacterium tuberculosis Culture Filtrate to Understand TB Pathogenesis
07:32

Preparation of Mycobacterium tuberculosis Culture Filtrate to Understand TB Pathogenesis

Published on: March 28, 2025

Protein secretion systems in Mycobacteria

Patricia A DiGiuseppe Champion1, Jeffery S Cox

  • 1Department of Microbiology and Immunology, Program in Microbial Pathogenesis and Host Defense, University of California, San Francisco, 600 16th Street, Campus Box 2200, San Francisco, CA 94143-2200, USA. Patricia.Champion@ucsf.edu

Cellular Microbiology
|May 1, 2007
PubMed

Insights

Mycobacteria utilize unique secretion systems, like the ESX-1 system, to export proteins through their thick cell envelope. This pathway is crucial for bacterial growth during infection and immune evasion by Mycobacterium tuberculosis.

Area of Science:

  • Microbiology
  • Cell Biology
  • Immunology

Background:

  • Mycobacteria possess a distinctive, hydrophobic cell envelope that acts as a protective barrier.
  • This thick envelope presents significant challenges for the efficient export of bacterial proteins.
  • Understanding protein secretion is vital for controlling mycobacterial infections.

Purpose of the Study:

  • To review the diverse protein secretion pathways in mycobacteria.
  • To highlight the significance of the ESX-1 secretion system.
  • To explore the role of ESX-1 in Mycobacterium tuberculosis pathogenesis and host immune interaction.

Main Methods:

  • Literature review of established and emerging protein secretion systems in mycobacteria.
  • Focus on comparative analysis of the general secretion pathway, Twin-Arginine Transporter, and ESX-1 system.
  • Synthesis of current research on the functional role of ESX-1 during infection.

Main Results:

  • Multiple protein secretion pathways exist in mycobacteria, adapted to their unique cell envelope.
  • The ESX-1 secretion system is essential for Mycobacterium tuberculosis growth in host environments.
  • ESX-1 plays a critical role in modulating the host immune response during infection.

Conclusions:

  • The ESX-1 system represents a key virulence factor in Mycobacterium tuberculosis.
  • Further research into mycobacterial secretion systems, particularly ESX-1, can reveal novel therapeutic targets.
  • Understanding these pathways is crucial for developing effective strategies against mycobacterial diseases.

More Related Videos

Enrichment of Native and Recombinant Extracellular Vesicles of Mycobacteria06:38

Enrichment of Native and Recombinant Extracellular Vesicles of Mycobacteria

Published on: December 8, 2023

Mycobacterium tuberculosis Extracellular Vesicle Enrichment through Size Exclusion Chromatography09:29

Mycobacterium tuberculosis Extracellular Vesicle Enrichment through Size Exclusion Chromatography

Published on: May 19, 2022

Related Concept Videos

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):...
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...
Bacterial Phylum Actinobacteria01:30

Bacterial Phylum Actinobacteria

Coryneform bacteria are gram-positive, aerobic, nonmotile rods that exhibit irregular, club-shaped, or V-shaped arrangements. Their V-shape results from snapping division, where the inner cell wall layer forms the cross-wall, while the outer layer remains intact until it ruptures on one side, causing the daughter cells to bend away.The primary genera are Corynebacterium and Arthrobacter. Corynebacterium includes diverse species, ranging from saprophytes to pathogens like Corynebacterium...
Overview of Secretory Vesicles01:33

Overview of Secretory Vesicles

Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Cytoskeletal Proteins in Bacteria01:29

Cytoskeletal Proteins in Bacteria

Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
Pulmonary Tuberculosis II01:28

Pulmonary Tuberculosis II

Tuberculosis, or TB, is a bacterial infectious disease caused by Mycobacterium tuberculosis. While its primary impact is on the lungs, leading to pulmonary tuberculosis, it can also affect various other organs, a condition referred to as extrapulmonary tuberculosis.
Here is a detailed explanation of its pathophysiology:
Transmission: The process begins when a person inhales droplet nuclei containing M. tuberculosis. These are typically released into the air when an individual with pulmonary or...