Molecular dynamics simulation strategies for protein-micelle complexes.

Area of Science:

• Biophysics
• Computational Chemistry
• Structural Biology

Background:

• Membrane protein structure and stability are highly sensitive to detergent environments.
• Mechanisms of protein-micelle interactions are poorly understood, hindering experimental work.
• Accurate construction of protein-micelle complexes for atomic simulations is challenging due to unknown detergent numbers.

Purpose of the Study:

• To develop and validate a method for constructing protein-micelle complexes for atomic simulations.
• To investigate the impact of varying detergent numbers on protein-detergent interactions.
• To provide a platform for atomic-level studies of membrane protein-detergent systems.

Main Methods:

• Utilized Micelle Builder in CHARMM-GUI for rapid construction of protein-micelle complexes.
• Performed atomic simulations of a voltage-dependent potassium channel's voltage-sensor domain and the antimicrobial peptide papiliocin.
• Varied the number of detergent molecules in the simulated complexes.

Main Results:

• Protein-detergent interactions stabilize significantly once the detergent number exceeds a specific threshold.
• Simulated results show consistency with experimental observations.
• Established a reliable method for building and simulating protein-micelle complexes.

Conclusions:

• The developed CHARMM-GUI approach enables efficient construction of protein-micelle complexes for simulations.
• A threshold in detergent number exists beyond which protein-detergent interactions become largely invariant.
• This work facilitates future atomic-level investigations into membrane protein behavior in detergent solutions.