[Intramolecular dynamics and functional activity of proteins]

Area of Science:

• Biophysics
• Biochemistry
• Molecular Biology

Context:

• Protein internal dynamics are crucial for biological functions.
• Understanding these dynamics is key to deciphering enzyme catalysis and cellular processes.
• Existing methods have limitations in probing millisecond dynamics, especially for membrane proteins.

Purpose:

• To analyze intramolecular protein dynamics in solution, membranes, and cells using tryptophan phosphorescence.
• To develop a novel phosphorescence method for investigating millisecond internal dynamics of membrane proteins.
• To demonstrate the functional significance of protein dynamics in various biological contexts.

Summary:

• Tryptophan phosphorescence at room temperature was used to study protein internal dynamics under diverse conditions (pH, ionic strength, temperature, ligand binding, proteolysis, etc.).
• The study highlights the functional role of low-frequency protein structural fluctuations in enzyme catalysis.
• A new phosphorescence technique enabled the investigation of millisecond internal dynamics in membrane proteins, revealing significant changes linked to biologically active substances, physiological factors, oxidative stress, and diseases like cancer and autoimmune disorders.

Impact:

• Provides a new method for studying membrane protein dynamics at the millisecond timescale.
• Reveals functionally significant shifts in protein dynamics associated with disease states and cellular signaling.
• Establishes a link between protein internal dynamics and enzyme catalysis, intracellular signaling, and disease pathogenesis.