PNNL

Abstract

Peroxiredoxins (Prx) are ubiquitous enzymes that reduce peroxides as part of antioxidant defenses and redox signaling. While Prx catalytic activity and sensitivity to hyperoxidative inactivation depend on their dynamic properties, there are few examples where their dynamics has been characterized by NMR spectroscopy. Here, we provide a foundation for studies of the solution properties of peroxiredoxin Q from the plant pathogen Xanthomonas campestris (XcPrxQ) by assigning the observable 1HN, 15N, 13Ca, 13Cß, and 13C´ chemical shifts for both the reduced (dithiol) and oxidized (disulfide) states. In the reduced state, most of the backbone amide resonances (149/152, 98%) can be assigned in the XcPrxQ 1H-15N HSQC spectrum. In contrast, a remarkable 51% (77) of these amide resonances are not visible in the 1H-15N HSQC spectrum of the disulfide state of the enzyme, indicating a substantial change in backbone dynamics associated with the formation of an intramolecular C48-C84 disulfide bond.