The first, 9.2ps-long, molecular dynamics simulation of the small protein bovine pancreatic trypsin inhibitor showed that protein interior is fluid-like in that the local atom motions have a diffusional character (McCammon, J. A., Gelin, B. R. & Karplus, M., 1977, Nature).

bpti1.mp4

Reproduction of the original simulation of BPTI (McCammon, Gelin & Karplus, Nature, 1977)

bpti2.mp4

With side chain motions

bpti3.mp4

With side chain and nearby water motions