4uzi

Publication Abstract from PubMed

Dye-decolorizing peroxidases (DyPs) such as AauDyPI from the fungus Auricularia auricula-judae are able to oxidize substrates of different kinds and sizes. A crystal structure of an AauDyPI-imidazole complex gives insight into the binding patterns of organic molecules within the heme cavity of a DyP. Several small N-containing heterocyclic aromatics are shown to bind in the AauDyPI heme cavity, hinting to susceptibility of DyPs to azole-based inhibitors similar to cytochromes P450. Imidazole is confirmed as a competitive inhibitor with regard to peroxide binding. In contrast, bulky substrates such as anthraquinone dyes are converted at the enzyme surface. In the crystal structure a substrate analog, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), binds to a tyrosine-rich hollow harboring Y25, Y147, and Y337. Spin trapping with a nitric oxide donor uncovers Y229 as an additional tyrosine-based radical center in AauDyPI. Multi-frequency EPR spectroscopy further reveals the presence of at least one intermediate tryptophanyl radical center in activated AauDyPI with W377 as the most likely candidate.

The toolbox of Auricularia auricula-judae dye-decolorizing peroxidase - Identification of three new potential substrate-interaction sites.,Strittmatter E, Serrer K, Liers C, Ullrich R, Hofrichter M, Piontek K, Schleicher E, Plattner DA Arch Biochem Biophys. 2014 Dec 23. pii: S0003-9861(14)00432-9. doi:, 10.1016/j.abb.2014.12.016. PMID:25542606^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.