Urea-induced drying of carbon nanotubes suggests existence of a dry globule-like transient state during chemical denaturation of proteins.
Atomistic dynamics simulations of purely hydrophobic carbon nanotubes in 8 M urea are performed to dissect the role of dispersion interactions in the denaturing power of urea. The enhanced population of urea and a paucity of water in proximity of nanotubes suggest that the stronger dispersion interaction of urea than water with nanotube triggers drying of its interior. The preferential intrusion of urea over water within nanotube interiors irrespective of their diameters directly implies a "dry globule"-like transient intermediate formation in the initial stage of protein unfolding in urea.
Das
Payel
P
Computational Biology Center, IBM Thomas J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, USA.
Zhou
Ruhong
R
D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D008968:Molecular Conformation; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011489:Protein Denaturation / Q000187:drug effects; D011506:Proteins / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D014508:Urea / Q000737:chemistry* / Q000494:pharmacology*; D014867:Water / Q000737:chemistry
D037742:Nanotubes, Carbon; D011506:Proteins; D012997:Solvents; D014867:Water; D014508:Urea