QUANTUM-CHEMICAL AND FREE-ENERGY SIMULATION ANALYSIS OF RETINAL CONFORMATIONAL ENERGETICS

Authors
BAUDRY J CROUZY S ROUX B SMITH JC
Citation
J. Baudry et al., QUANTUM-CHEMICAL AND FREE-ENERGY SIMULATION ANALYSIS OF RETINAL CONFORMATIONAL ENERGETICS, Journal of chemical information and computer sciences, 37(6), 1997, pp. 1018-1024
Citations number
23
Categorie Soggetti
Information Science & Library Science","Computer Application, Chemistry & Engineering","Computer Science Interdisciplinary Applications",Chemistry,"Computer Science Information Systems
Journal title
Journal of chemical information and computer sciences → ACNP
ISSN journal
00952338
Volume
37
Issue
6
Year of publication
1997
Pages
1018 - 1024
Database
ISI
SICI code
0095-2338(1997)37:6<1018:QAFSAO>2.0.ZU;2-O
Abstract
Ab initio quantum chemical and free energy molecular dynamics calculat ions are performed to examine energy differences between the all-trans and (13,15)cis conformers of retinal, i.e., those populated in the da rk-adapted stale of bacteriorhodopsin. The quantum chemical results ar e used to derive an empirical force field that is used to calculate an adiabatic potential energy map for rotation about the bonds concerned . The same potential function is used in restrained molecular dynamics free energy calculations, with and without umbrella sampling. The sim ulation model yields a free energy of the (13,15)cis isomer similar to 2.1 kcal/mol higher than that of the all-trans species.