The molecular determinants of the increased reduction potential of the rubredoxin domain of rubrerythrin relative to rubredoxin.

ABSTRACT: Based on the crystal structures, three possible sequence determinants have been suggested as the cause of a 285 mV increase in reduction potential of the rubredoxin domain of rubrerythrin over rubredoxin by modulating the polar environment around the redox site. Here, electrostatic calculations of crystal structures of rubredoxin and rubrerythrin and molecular dynamics simulations of rubredoxin wild-type and mutants are used to elucidate the contributions to the increased reduction potential. Asn(160) and His(179) in rubrerythrin versus valines in rubredoxins are predicted to be the major contributors, as the polar side chains contribute significantly to the electrostatic potential in the redox site region. The mutant simulations show both side chains rotating on a nanosecond timescale bet

SUBMITTER: Luo Y 

PROVIDER: S-EPMC2820635 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature