Behavior regulation of adsorbed proteins via hydroxyapatite surface texture control

Area of Science:

• Biomaterials Science
• Computational Biophysics
• Surface Chemistry

Background:

• Nanoscale interfaces critically affect protein behavior, a key factor in biomaterial design.
• Understanding protein-surface interactions is vital for developing effective biomedical implants and therapies.

Purpose of the Study:

• To investigate the dynamic interactions of bone morphogenetic protein-7 (BMP-7) with various hydroxyapatite (HAP) surface textures.
• To elucidate how HAP surface topography influences BMP-7 adsorption, conformation, and electron transfer dynamics.

Main Methods:

• Utilized molecular dynamics (MD) and steered molecular dynamics (SMD) simulations to analyze protein-surface interactions.
• Employed quantum mechanics (QM) calculations to investigate electronic interactions during protein adsorption.
• Analyzed interaction energy curves to quantify protein-surface binding characteristics.

Main Results:

• SMD simulations revealed detailed dynamic behaviors of BMP-7, correlating with HAP surface textures.
• Identified specific adsorptive residues and interaction intensities influenced by HAP surface topography.
• Observed significant electron transfer from HAP to BMP-7 during adsorption, particularly in system 010+a, which showed the largest conformational change.

Conclusions:

• HAP surface texture plays a crucial role in modulating BMP-7's dynamic behavior and conformational changes.
• Surface-engineering of HAP materials offers a pathway to control protein adsorption and function at the nanoscale.
• These findings have implications for designing advanced biomaterials with tailored protein interactions.