6atj

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spinqualitylabelsall models 6atj, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

RECOMBINANT HORSERADISH PEROXIDASE C COMPLEX WITH FERULIC ACID

Overview

We have solved the x-ray structures of the binary horseradish peroxidase, C-ferulic acid complex and the ternary horseradish peroxidase, C-cyanide-ferulic acid complex to 2.0 and 1.45 A, respectively. Ferulic, acid is a naturally occurring phenolic compound found in the plant cell, wall and is an in vivo substrate for plant peroxidases. The x-ray, structures demonstrate the flexibility and dynamic character of the, aromatic donor binding site in horseradish peroxidase and emphasize the, role of the distal arginine (Arg(38)) in both substrate oxidation and, ligand binding. Arg(38) hydrogen bonds to bound cyanide, thereby, contributing to the stabilization of the horseradish peroxidase-cyanide, complex and suggesting that the distal arginine will be able to contribute, with a similar interaction during stabilization of a bound peroxy, transition state and subsequent O-O bond cleavage. The catalytic arginine, is additionally engaged in an extensive hydrogen bonding network, which, also includes the catalytic distal histidine, a water molecule and, Pro(139), a proline residue conserved within the plant peroxidase, superfamily. Based on the observed hydrogen bonding network and previous, spectroscopic and kinetic work, a general mechanism of peroxidase, substrate oxidation is proposed.

About this Structure

6ATJ is a Single protein structure of sequence from Armoracia rusticana with CA, HEM and FER as ligands. Active as Peroxidase, with EC number 1.11.1.7 Full crystallographic information is available from OCA.

Reference

The structures of the horseradish peroxidase C-ferulic acid complex and the ternary complex with cyanide suggest how peroxidases oxidize small phenolic substrates., Henriksen A, Smith AT, Gajhede M, J Biol Chem. 1999 Dec 3;274(49):35005-11. PMID:10574977

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