Title Chicken Lysozyme Dynamics
Contributors: Carol B. Post and Martin Karplus
Reference: J. Mol. Biol. 1986, 190:455-479; J. Am. Chem. Soc. 1986, 108:1317-1319
This movie is a digitized copy of a 16 mm color film shot in 1984 directly from an Evans and Sutherland PS300 graphics monitor and using the graphics program HYDRA, written by Rod Hubbard. The scenes are extracted from the first molecular dynamics trajectory of a protein run on a supercomputer, a CRAY-1S. This molecular dynamics simulations of hen egg-white lysozyme showed atomic details of internal motions required for processes such as exchange between hydrogen-bonding partners of an a helix residue, flipping of a large side chain of a buried tryptophan residue, and fluctuations of protein interactions with the substrate. The movie zooms-in to ring D of a polysaccharide substrate (light green) to illustrate fluctuating hydrogen bonds of multiple substrate oxygen atoms (red) with protonated Glu 35, a key catalytic residue. Discovery of particular enzyme-substrate interactions lead to the proposal for a new mechanism of hydrolysis by lysozyme.