Related Experiment Video
Updated: Jul 13, 2026
06:45
Transmembrane Domain Oligomerization Propensity determined by ToxR Assay
Published on: May 26, 2011
A mutational study of transmembrane helix-helix interactions
Alexander Prodöhl1, Mathias Weber, Carolin Dreher
1Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung, Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany.
Biochimie
|August 11, 2007
Summary
Studying transmembrane helix interactions requires careful consideration of the environment. Detergent properties significantly influence helix interactions, particularly those with polar residues.
Area of Science:
- Biochemistry and biophysics
- Membrane protein structure and function
Background:
- Transmembrane alpha-helix interactions are crucial for protein function.
- Various methods exist to study these interactions, often using SDS-PAGE.
- The influence of the surrounding environment on these interactions is not fully understood.
Purpose of the Study:
- To compare the stability of a transmembrane helix-helix interaction in a biological membrane versus SDS.
- To investigate the impact of detergent properties on transmembrane helix interactions.
Main Methods:
- Determining the stability of the PsbF transmembrane helix dimer.
- Conducting measurements in both a biological membrane and sodium dodecyl sulfate (SDS).
Main Results:
- The stability of the transmembrane helix-helix interaction was found to be dependent on the environment.
- Detergent properties, specifically in SDS, significantly influenced the measured stability.
- This influence was particularly pronounced for transmembrane domains containing polar residues.
Conclusions:
- The environment is critical when studying transmembrane helix interactions.
- Detergent choice and properties can significantly alter the interpretation of helix interaction stability.
- Results highlight the importance of considering the experimental conditions for accurate analysis of membrane protein behavior.
Related Concept Videos
01:09Multi-pass Transmembrane Proteins and β-barrels
In multi-pass transmembrane proteins, the polypeptide chain crosses the membrane more than once. The transmembrane polypeptide chain either forms an α-helix or β-strand structure. α-Helix containing multi-pass transmembrane proteins are ubiquitous, whereas β-strand containing ones are mainly found in gram-negative bacteria, mitochondria, and chloroplasts.
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
01:25Single-pass Transmembrane Proteins
Integral membrane proteins are tightly associated with the cell membrane and play a crucial role in cell communication, signaling, adhesion, and transport of the molecules. Some integral membrane proteins are present only in the membrane monolayer. For example, the enzyme fatty acid amide hydrolase is present in the cytoplasmic side of the membrane monolayer. In contrast, another type of integral membrane protein, also known as a transmembrane protein, spans across the membrane. Transmembrane...
01:29Insertion of Multi-pass Transmembrane Proteins in the RER
The rough ER membrane synthesizes, assembles, and embeds transmembrane proteins in diverse topologies. These proteins function as transporters or channels and can remain in the ER membrane or are sent to the Golgi complex, lysosome, and cell membrane.
The multipass transmembrane proteins are the type IV integral membrane proteins with multiple topogenic sequences determining their spatial arrangement in the ER membrane. Nearly all multipass proteins lack a cleavable signal sequence and use...
The multipass transmembrane proteins are the type IV integral membrane proteins with multiple topogenic sequences determining their spatial arrangement in the ER membrane. Nearly all multipass proteins lack a cleavable signal sequence and use...
01:26Insertion of Single-pass Transmembrane Proteins in the RER
Integral membrane proteins are proteins adhered to the lipid bilayer of a cell organelle or membrane. They can be of two types: transmembrane integral proteins that span the lipid bilayer and monotopic proteins that are attached to either side of the membrane but do not pass through it.
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
01:19Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...