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TcVP1 are good candidates for development of a novel strategy for the treatment of
dye wastewater.
It is also reported that the putative oxidative cycle of fungal DyPs is largely
equivalent to that found in other peroxidases. Yoshida et al. ( 2011 ) proposed a
swinging mechanism of a distal aspartate residue during Compound I formation, as
re
rst step, H 2 O 2 enters the heme cavity of the enzyme in
resting state, where it displaces a water molecule that occupies the sixth ferric iron
coordination site of the protoporphyrin IX system. A distal basic amino acid residue
mediates the rearrangement of a proton in H 2 O 2 . In peroxidases, the base residue is
a histidine, whereas in DyPs, this key residue is substituted by an aspartate. The
heme molecule is then oxidized to the radical-cationic oxoferryl species Compound
I by two-fold single electron transfer, releasing a water molecule. Two electrons are
successively drawn from substrate molecules, to from their oxidized counterparts.
Concomitantly, the heme is stepwise reduced back to its initial oxidation state,
leading to the resting phase of the enzyme in this process.
ected in Fig. 5 . In the
Fig. 5 Catalytic features of a DyP-type peroxidase
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