Related Experiment Video
Updated: May 7, 2026
10:37
Protein Complex Affinity Capture from Cryomilled Mammalian Cells
Published on: December 9, 2016
Amino acid capture by aqueous interfaces. Implications for biological uptake
Marilia T C Martins-Costa1, Manuel F Ruiz-Lopez
1SRSMC, UMR 7565, University of Lorraine , BP 70239, 54506, Vandoeuvre-les-Nancy, France.
The Journal of Physical Chemistry. B
|October 8, 2013
Summary
Amino acid interactions at water-organic interfaces are crucial for biological processes. This study reveals how side-chain hydrophobicity influences amino acid phase transfer, with implications for membrane protein stability and transport.
Area of Science:
- Biochemistry
- Physical Chemistry
- Computational Biology
Background:
- Amino acid interactions with hydrophobic interfaces are vital for biological functions like passive transport and membrane protein structure.
- Current understanding of these interactions, particularly concerning phase transfer mechanisms, remains limited.
Purpose of the Study:
- To investigate the thermochemistry and dynamics of simple aliphatic amino acids (glycine and valine) at a water-organic interface.
- To elucidate the role of side-chain hydrophobicity in the phase transfer mechanism of amino acids.
Main Methods:
- Utilized Born-Oppenheimer molecular dynamics simulations.
- Focused on analyzing the energetics and dynamics of amino acid transfer across the interface.
Main Results:
- Neutral amino acid tautomers show increased interface affinity with greater side-chain hydrophobicity.
- Both neutral and zwitterionic valine, and neutral glycine, exhibit significant interface affinity.
- Neutral and zwitterionic tautomers are nearly isoergonic in the organic layer, suggesting a two-step transfer mechanism involving neutralization.
Conclusions:
- The findings suggest a two-step phase transfer mechanism for amino acids across water-organic interfaces.
- Differences in energetics and dynamics between glycine and valine transfer are predicted, with potential biological relevance for membrane transport and protein stability.
More Related Videos
08:232 in 1: One-step Affinity Purification for the Parallel Analysis of Protein-Protein and Protein-Metabolite Complexes
Published on: August 6, 2018
14:43Microfluidic On-chip Capture-cycloaddition Reaction to Reversibly Immobilize Small Molecules or Multi-component Structures for Biosensor Applications
Published on: September 23, 2013
Related Concept Videos
01:17Pore Transport and Ion-Pair Transport
Pore transport and ion-pair formation are critical mechanisms for the absorption and distribution of drugs in the body.
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
02:04Protein-protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
01:18Amino Acid Catabolism
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
02:40Ligand Binding Sites
Proteins are dynamic macromolecules that carry out a wide variety of essential processes; however, the activities of most proteins depend on their interactions with other molecules or ions, known as ligands.
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
01:22Inorganic Nitrogen Assimilation
Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme nitrate reductase...
01:44The Significance of Membrane Transport
The transport of solutes across the cell membrane is essential for metabolic processes, like maintaining cell size and volume, generating the action potential, exchanging nutrients and gases, etc. Membrane transport can be either passive or active. It can be simple diffusion, facilitated, or mediated transport aided by transport proteins such as transporters and channels.
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...