On the nature of low-frequency vibrational modes in globular protein molecules immersed in water

Recent vibrational normal mode analysis of globular protein molecules (in vacuum) has shown that they have characteristic low-frequency (≈ 2–5 cm⁻¹) modes. It is shown that when the molecules are immerséd in water the modes are strongly red-shifted and damped. The implications of this result are briefly discussed.