Substrate-triggered formation and remarkable stability of the C-H bond-cleaving chloroferryl intermediate in the aliphatic halogenase, SyrB2.

ABSTRACT: Aliphatic halogenases activate O(2), cleave alpha-ketoglutarate (alphaKG) to CO(2) and succinate, and form haloferryl [X-Fe(IV)O; X = Cl or Br] complexes that cleave aliphatic C-H bonds to install halogens during the biosynthesis of natural products by non-ribosomal peptide synthetases (NRPSs). For the related alphaKG-dependent dioxygenases, it has been shown that reaction of the Fe(II) cofactor with O(2) to form the C-H bond-cleaving ferryl complex is "triggered" by binding of the target substrate. In this study, we have tested for and defined structural determinants of substrate triggering (ST) in the halogenase, SyrB2, from the syringomycin E biosynthetic NRPS of Pseudomonas syringae B301D. As for other halogenases, the substrate of SyrB2 is complex, consisting of l-Thr tethered via a t

SUBMITTER: Matthews ML 

PROVIDER: S-EPMC2684568 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature