Computational Study on the Thermal Conductivity of a Protein

Protein molecules are thermallyfluctuating and tightly packed amino acidresidues strongly interact with each other. Such interactions are characterized in terms ofheat current at the atomic level. We calculated the thermal conductivity of a smallglobular protein, villin headpiece subdomain, based on the linear response theory usingequilibrium molecular dynamics simulation. The value of its thermal conductivity was 0.3 +/- 0.01 [W m-1K-1], which is in good agreement with experimental and computationalstudies on the other proteins in the literature. Heat current along the main chain wasdominated by local vibrations in the polypeptide bonds, with amide I, II, III, and A bandson the Fourier transform of the heat current autocorrelation function