Factors that distort the heme structure in Heme-Nitric Oxide/OXygen-Binding (H-NOX) protein domains. A theoretical study.

ABSTRACT: DFT and dispersion-corrected DFT calculations were carried out to probe the factors that distort the heme structure in Heme-Nitric oxide/OXygen-binding (H-NOX) protein domains. Various model systems that include heme, heme+surrounding residues, and heme+surrounding residues+additional protein environment were examined; the latter system was calculated with a quantum mechanics/molecular mechanics (QM/MM) method. The computations were extended to a myoglobin (Mb) protein, in which the heme structure is quite planar, in contrast to that in H-NOX. The natural tendency of the heme is to be planar. The strong structural distortion in H-NOX is mainly brought about by the intermolecular interactions between the whole heme molecule (heme ring plus its peripheral substituents) and the surrounding re

SUBMITTER: Liao MS 

PROVIDER: S-EPMC3518654 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature