@article{Kalkan23, author={{\"O}zlem Kalkan and Sravya Kantamneni and Lea Brings and Huijong Han and Richard Bean and Adrian P. Mancuso and Faisal H. M. Koua}, title={Heterologous expression, purification and structural features of native \emph{Dictyostelium discoideum} dye-decolorizing peroxidase bound to a natively incorporated heme}, journal={Front. Chem.}, volume={11}, pages={1220543}, year={2023}, keywords={European XFEL;}, url={https://doi.org/10.3389/fchem.2023.1220543}, doi={10.3389/fchem.2023.1220543}, abstract={The \emph{Dictyostelium discoideum} dye-decolorizing peroxidase (\emph{Dd}DyP) is a newly discovered peroxidase, which belongs to a unique class of heme peroxidase family that lacks homology to the known members of plant peroxidase superfamily. \emph{Dd}DyP catalyzes the H$_2$O$_2$-dependent oxidation of a wide-spectrum of substrates ranging from polycyclic dyes to lignin biomass, holding promise for potential industrial and biotechnological applications. To study the molecular mechanism of \emph{Dd}DyP, highly pure and functional protein with a natively incorporated heme is required, however, obtaining a functional DyP-type peroxidase with a natively bound heme is challenging and often requires addition of expensive biosynthesis precursors. Alternatively, a heme \emph{in vitro} reconstitution approach followed by a chromatographic purification step to remove the excess heme is often used. Here, we show that expressing the \emph{Dd}DyP peroxidase in $\times$2 YT enriched medium at low temperature (20$^\circ$C), without adding heme supplement or biosynthetic precursors, allows for a correct native incorporation of heme into the apo-protein, giving rise to a stable protein with a strong Soret peak at 402 nm. Further, we crystallized and determined the native structure of \emph{Dd}DyP at a resolution of 1.95 \AA, which verifies the correct heme binding and its geometry. The structural analysis also reveals a binding of two water molecules at the distal site of heme plane bridging the catalytic residues (Arg239 and Asp149) of the GXXDG motif to the heme-Fe(III) via hydrogen bonds. Our results provide new insights into the geometry of native \emph{Dd}DyP active site and its implication on DyP catalysis.}
}