Crystal structures of two novel dye-decolorizing peroxidases reveal a beta-barrel fold with a conserved heme-binding motif.

Abstract

BtDyP from Bacteroides thetaiotaomicron (strain VPI-5482) and TyrA from Shewanella oneidensis are dye-decolorizing peroxidases (DyPs), members of a new family of heme-dependent peroxidases recently identified in fungi and bacteria. Here, we report the crystal structures of BtDyP and TyrA at 1.6 and 2.7 A, respectively. BtDyP assembles into a hexamer, while TyrA assembles into a dimer; the dimerization interface is conserved between the two proteins. Each monomer exhibits a two-domain, alpha+beta ferredoxin-like fold. A site for heme binding was identified computationally, and modeling of a heme into the proposed active site allowed for identification of residues likely to be functionally important. Structural and sequence comparisons with other DyPs demonstrate a conservation of putative heme-binding residues, including an absolutely conserved histidine. Isothermal titration calorimetry experiments confirm heme binding, but with a stoichiometry of 0.3:1 (heme:protein).

Cite this paper

@article{Zubieta2007CrystalSO, title={Crystal structures of two novel dye-decolorizing peroxidases reveal a beta-barrel fold with a conserved heme-binding motif.}, author={Chloe Zubieta and S. Sri Krishna and Mili Kapoor and Piotr Kozbial and Daniel McMullan and Herbert L. Axelrod and Mitchell D. Miller and Polat Abdubek and Eileen Ambing and Tamara Astakhova and Dennis W. Carlton and Hsiu-Ju Chiu and Thomas Clayton and Marc C. Deller and Lian Duan and Marc-Andr{\'e} Elsliger and Julie Feuerhelm and Slawomir K. Grzechnik and Joanna Hale and Eric N Hampton and Gye Won Han and Lukasz Jaroszewski and Kevin Jin and Heath E. Klock and Mark W. Knuth and Abhinav Kumar and David C. Marciano and Andrew T. Morse and Edward Nigoghossian and Linda Okach and Silvya Oommachen and Ron Reyes and Christopher L. Rife and Paul R. Schimmel and Henry van den Bedem and Dana Weekes and Aprilfawn White and Qingping Xu and Keith O Hodgson and John C. Wooley and Ashley Deacon and Adam Godzik and Scott A. Lesley and Ian A. Wilson}, journal={Proteins}, year={2007}, volume={69 2}, pages={223-33} }