Related Experiment Video
Updated: Jul 1, 2026
06:48
Single-Molecule Measurement of Protein Interaction Dynamics Within Biomolecular Condensates
Published on: January 5, 2024
Kinetic model for salt-induced protein deactivation.
James M Broering1, Andreas S Bommarius
1School of Chemical and Biomolecular Engineering, Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, GA 30332-0363, USA.
The Journal of Physical Chemistry. B
|September 12, 2008
Summary
This study introduces a new model to predict protein degradation in salt solutions, crucial for pharmaceutical stability and biocatalyst performance. The model quantifies how salts influence protein function, enhancing shelf-life predictions.
Area of Science:
- Biochemistry
- Physical Chemistry
- Protein Science
Background:
- Understanding protein stability in solution is vital for pharmaceuticals and biocatalysts.
- Current models lack quantitative descriptions of salt and buffer effects on protein degradation.
- Hofmeister effects significantly impact protein behavior but require detailed mechanistic understanding.
Purpose of the Study:
- To develop a quantitative model describing protein deactivation influenced by salts and buffer components.
- To elucidate the role of ion hydration and chaotropic/kosmotropic effects on protein stability.
- To provide a framework for predicting protein shelf-life and biocatalyst operating life.
Main Methods:
- Modeling protein deactivation as competing chaotrope-dependent and ion hydration-independent processes.
- Fitting experimental data using a four-parameter model including protein-dependent constants and ion hydration coefficients.
- Experimental validation using horse-liver alcohol dehydrogenase (HL-ADH), alpha-chymotrypsin, and monomeric red fluorescent protein (mRFP).
Main Results:
- A four-parameter model accurately describes protein deactivation in aqueous salt solutions.
- The model quantifies Hofmeister effects on various proteins.
- Calculated kinetic m values indicate the transition state of deactivation resembles the unfolded state in chaotropic solutions and the native state under kinetic control.
Conclusions:
- Ion hydration effects are critical for explaining Hofmeister effects on proteins.
- The developed model provides a kinetic equivalent of Wyman linkage for calculating m values.
- This work offers a method to predict protein stability across various salt compositions and temperatures.
More Related Videos
Related Concept Videos
01:13Induced-fit Model
Most chemical reactions in cells require enzymes—biological catalysts that speed up the reaction without being consumed or permanently changed. They reduce the activation energy needed to convert the reactants into products. Enzymes are proteins, that usually work by binding to a substrate—a reactant molecule that they act upon.
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical characteristics of...
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical characteristics of...
01:58Mechanical Protein Functions
Proteins perform many mechanical functions in a cell. These proteins can be classified into two general categories- proteins that generate mechanical forces and proteins that are subjected to mechanical forces. Proteins providing mechanical support to the structure of the cell, such as keratin, are subjected to mechanical force, whereas proteins involved in cell movement and transport of molecules across cell membranes, such as an ion pump, are examples of generating mechanical force.
01:48ATP Synthase: Mechanism
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
01:22Amplifying Signals via Enzymatic Cascade
When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
01:13Physiological Pharmacokinetic Models: Assumption with Protein Binding
Physiological models with protein binding in pharmacokinetics offer a sophisticated approach to understanding drug disposition. These models consider drug-protein interactions, enabling them to effectively predict drug concentrations in different organs and tissues. This precision aids in accurate drug dosing, providing a significant advantage over conventional models. A key process within these models is equilibration, which ensures that drug concentrations achieve a steady state within the...
01:28Protein Denaturation
The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. Folding of the polypeptide chain takes place under specific conditions that energetically favor the folded conformation. In contrast, protein denaturation occurs spontaneously under unfavorable conditions that disrupt the integrity of the folded conformation. Thus, the chemical and physical environment of a protein, such as significant changes in pH...