Related Experiment Video

Updated: May 10, 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

Backbone and side-chain assignments of an effector membrane localization domain from Vibrio vulnificus MARTX toxin

Michael C Brothers1, Brett Geissler, Grant S Hisao

  • 1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.

Biomolecular NMR Assignments
|June 15, 2013
PubMed

Insights

This study presents chemical shift assignments for the Vibrio vulnificus MARTX toxin’s membrane localization domain (MLD(VvDUF5)). These assignments support a four-helix bundle structure, aiding future structural and dynamic studies.

Area of Science:

  • Biochemistry
  • Structural Biology
  • Microbiology

Background:

  • The MARTX toxin from Vibrio vulnificus is a key virulence factor.
  • The membrane localization domain (MLD) of effectors like VvDUF5 is crucial for toxin function.
  • Understanding the structure of MLDs is essential for developing targeted inhibitors.

Purpose of the Study:

  • To provide complete (1)H, (13)C, and (15)N chemical shift assignments for the MLD(VvDUF5) in solution.
  • To analyze the secondary structure of MLD(VvDUF5) using NMR data.
  • To compare the predicted structure with homologous domains from other bacterial toxins.

Main Methods:

  • Nuclear Magnetic Resonance (NMR) spectroscopy was used to collect (1)H, (13)C, and (15)N chemical shift data.
  • TALOS+ software was employed for secondary chemical shift analysis.
  • Structure homology modeling was performed using MLDs from Pasteurella multocida toxin (PMT) and clostridial toxins (TcdB, TcsL) as templates.

Main Results:

  • Successfully assigned 97% of backbone and side-chain carbon atoms and 96% of backbone residues.
  • Secondary chemical shift analysis confirmed a four-helix bundle structure for MLD(VvDUF5).
  • The observed helical structure aligns with predictions from homology modeling.

Conclusions:

  • The provided chemical shift assignments form a foundation for future structural and dynamic studies of MLD(VvDUF5).
  • The confirmed four-helix bundle structure provides insights into the membrane localization mechanism of MARTX toxin.
  • This work contributes to the understanding of bacterial toxin structure-function relationships.

More Related Videos

Monitoring the Assembly of a Secreted Bacterial Virulence Factor Using Site-specific Crosslinking11:33

Monitoring the Assembly of a Secreted Bacterial Virulence Factor Using Site-specific Crosslinking

Published on: December 17, 2013

Membrane-SPINE: A Biochemical Tool to Identify Protein-protein Interactions of Membrane Proteins In Vivo10:53

Membrane-SPINE: A Biochemical Tool to Identify Protein-protein Interactions of Membrane Proteins In Vivo

Published on: November 7, 2013

Related Concept Videos

Transducer Mechanism: Enzyme-Linked Receptors01:27

Transducer Mechanism: Enzyme-Linked Receptors

Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:
Membrane Domains01:18

Membrane Domains

The membrane domains concentrate specific lipids and proteins at one place within the membrane, which helps in cell signaling, adhesion, and other critical cellular processes. These domains can differ in size, composition, function, and lifespan.
Protein Domains
The membrane comprises a group of distinct proteins responsible for carrying out a cell's specific function. For example, the plasma membrane of the human sperm, or a single germ cell, contains a unique set of proteins in the anterior...
Tail-anchoring of Proteins in the ER Membrane01:45

Tail-anchoring of Proteins in the ER Membrane

Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
Membrane Proteins01:30

Membrane Proteins

Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport proteins, and they function as either channels for the material or as carriers themselves. Channel proteins have hydrophilic domains exposed to the intracellular and extracellular fluids and a hydrophilic channel through their core that provides a hydrated opening for solutes to pass through the membrane layers. Passage through the channel allows...
Membrane Proteins01:30

Membrane Proteins

Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport proteins, and they function as either channels for the material or as carriers themselves. Channel proteins have hydrophilic domains exposed to the intracellular and extracellular fluids and a hydrophilic channel through their core that provides a hydrated opening for solutes to pass through the membrane layers. Passage through the channel allows...
Mechanisms of Membrane Domain Formation00:59

Mechanisms of Membrane Domain Formation

Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...