Roles of High-valent Hemes and pH Dependence in Halite Decomposition Catalyzed by Chlorite Dismutase from Dechloromonas aromatica.

ABSTRACT: The heme-based chlorite dismutases catalyze the unimolecular decomposition of chlorite (ClO₂ ^-) to yield Cl^- and O₂. The work presented here shows that chlorite dismutase from Dechloromonas aromatica (DaCld) also catalyzes the decomposition of bromite (BrO₂ ^-) with the evolution of O₂ (k _cat = (2.0±0.2)×10² s^-1; k _cat/K _M = (1.2±0.2)×10⁵ M^-1 s^-1 at pH 5.2). Stopped-flow studies of this BrO₂ ^- decomposition as a function of pH show that 1) the two-electron oxidized heme, compound I (Cpd I), is the primary accumulating heme intermediate during O₂ evolution in aci

SUBMITTER: Geeraerts Z 

PROVIDER: S-EPMC9328492 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature