HIV-1 protease flaps spontaneously open and reclose in molecular dynamics simulations.

ABSTRACT: We report unrestrained, all-atom molecular dynamics simulations of HIV-1 protease that sample large conformational changes of the active site flaps. In particular, the unliganded protease undergoes multiple conversions between the "closed" and "semiopen" forms observed in crystal structures of inhibitor-bound and unliganded protease, respectively, including reversal of flap "handedness." Simulations in the presence of a cyclic urea inhibitor yield stable closed flaps. Furthermore, we observe several events in which the flaps of the unliganded protease open to a much greater degree than observed in crystal structures and subsequently return to the semiopen state. Our data strongly support the hypothesis that the unliganded protease predominantly populates the semiopen conformation, with clo

SUBMITTER: Hornak V 

PROVIDER: S-EPMC1347991 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature