fulltext.study @t Gmail

Characterization of pyranose dehydrogenase from Agaricus meleagris and its application in the C-2 specific conversion of d-galactose

Paper ID Volume ID Publish Year Pages File Format Full-Text
24809 43538 2008 9 PDF Available
Title
Characterization of pyranose dehydrogenase from Agaricus meleagris and its application in the C-2 specific conversion of d-galactose
Abstract

Pyranose dehydrogenase (PDH) of the mushroom Agaricus meleagris was purified from mycelial culture media to substantial homogeneity using ion-exchange and hydrophobic interaction chromatography. The native enzyme is a monomeric polypeptide with a molecular mass of 66,547 Da as determined by matrix-assisted laser desorption/ionisation mass spectrometry containing ∼7% carbohydrate and covalently bound flavin adenine dinucleotide. The enzyme exhibited a broad sugar substrate tolerance, oxidizing different aldopyranoses to the corresponding C-2 or C-2,3 (di)dehydro sugars. Preferred electron donors with the highest kcat/Km values were major sugar constituents of cellulose and hemicellulose, namely d-glucose, d-galactose, l-arabinose, d-xylose and cellobiose. This indicates a possible physiological role of the enzyme in lignocellulose breakdown. PDH showed no detectable activity with oxygen, and its reactivity towards electron acceptors was limited to various substituted benzoquinones and complexed metal ions, with the ferricenium ion and the benzoquinone imine 2,6-dichloroindophenole displaying the highest kcat/Km. The enzyme catalyzed in up to 95% yields the regiospecific conversion of d-galactose to 2-dehydro-d-galactose, an intermediate in a possible biotechnologically interesting process for redox isomerization of d-galactose to the prebiotic sugar d-tagatose.

Keywords
Pyranose dehydrogenase; Sugar oxidoreductase; Galactose conversion; Enzyme technology
First Page Preview
Characterization of pyranose dehydrogenase from Agaricus meleagris and its application in the C-2 specific conversion of d-galactose
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Biotechnology - Volume 133, Issue 3, 1 February 2008, Pages 334–342
Authors
, , , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us