Biological water: Its vital role in macromolecular structure and function

Area of Science:

• Biophysics
• Structural Biology
• Physical Chemistry

Background:

• Water within cells and tissues behaves differently from bulk water due to structural confinement.
• Cellular structures influence water molecule properties, including dielectric susceptibility and relaxation frequency.
• These alterations impact macromolecular interactions and protein hydration.

Purpose of the Study:

• To elucidate the distinct characteristics of biological water compared to ordinary water.
• To explore how cellular environments structure water molecules.
• To investigate the role of water's anisotropic hydration shells in protein function and denaturation detection.

Main Methods:

• Analysis of water molecule behavior at hydrophilic and hydrophobic sites.
• Examination of polarization fields generated by structured water.
• Correlation of hydration shell anisotropy with enzyme function and protein unfolding.

Main Results:

• Cellular confinement induces structural effects on water, lowering dielectric susceptibility and red-shifting relaxation frequency.
• Differential behavior of water at hydrophilic versus hydrophobic sites leads to anisotropic hydration shells around proteins.
• Hydration shell anisotropy is crucial for enzyme activity and serves as an indicator of protein denaturation.

Conclusions:

• Biological water's properties are significantly modulated by its cellular environment.
• The anisotropy of protein hydration shells is vital for biological processes and detecting structural integrity.
• Studying biological water dynamics offers insights into cellular component structure and function.