Crystal structures of the CO and NOBound DosS GAF-A domain and implications for DosS signaling in Mycobacterium tuberculosis.

ABSTRACT: DosS is a sensor in Mycobacterium tuberculosis that differentially responds to O₂, NO, and CO, as well as to changes in the redox state of the prosthetic heme iron atom. The ferrous protein and its Fe(II)NO and Fe(II)CO complexes undergo autophosphorylation and subsequently transfer the phosphate group to DosR, a nuclear factor, to activate it. In contrast, autophosphorylation is negligible with the ferric protein and the Fe(II)O₂ complex. To clarify the basis for this differential response to gases, we have determined the crystal structures of the NO and COcomplexes of the DosS GAF-A domain, which contains the heme to which the gases bind. Comparison of these crystal structures with those reported for the phosphorylation-inactive ferric GAF-A domain suggest that the

SUBMITTER: Madrona Y 

PROVIDER: S-EPMC5121028 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature