title: Simulations of dynamical properties of a Michaelis complex: porcine pancreatic elastase and the hexapeptide, Thr-Pro-n Val-Leu-Tyr-Thr.
abstract: Molecular dynamic simulations (30ps) of the Michaelis complex of hexapeptide (Thr-Pro-nVal-Leu-Tyr-Thr) bound to porcine pancreatic elastase (PPE) hydrated by about 2000 water molecules have been performed using the AMBER 3.0 program package. Dynamical properties of the conformation of the active site have been examined. A comparison with previously reported simulations of native PPE shows that after the substrate is bound, the catalytically crucial H-bond between O gamma-H group of (Ser 195) and nitrogen N epsilon (His 57) is more readily formed. These results show, however, that the H-bond does not adopt the most favorable conformation. The O gamma-H group of Ser 195 has a statistical preference for an attractive interaction with the O = C carbonyl (Ser 214) rather than the nitrogen N epsilon (His 57).
authors.affiliation: Texas A & M University, Department of Biochemistry and Biophysics, College Station 77843.
authors.forename: M
authors.initials: M
authors.lastname: Geller
authors.forename: S M
authors.initials: SM
authors.lastname: Swanson
authors.forename: E F
authors.initials: EF
authors.lastname: Meyer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010196:Pancreatic Elastase / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D013552:Swine
chemical_list: D010196:Pancreatic Elastase