Is cellobiose dehydrogenase from Phanerochaete chrysosporium a lignin degrading enzyme?
2000 (English)In: Biochimica et Biophysica Acta - Protein Structure and Molecular Enzymology, ISSN 0167-4838, Vol. 1480, no 02-jan, 83-91 p.Article in journal (Refereed) Published
Cellobiose dehydrogenase (CDH) is an extracellular redox enzyme of ping-pong type, i.e. it has separate oxidative and reductive half reactions. Several wood degrading fungi produce CDH, but the biological function of the enzyme is not known with certainty. It can, however, indirectly generate hydroxyl radicals by reducing Fe3+ to Fe2+ and O-2 to H2O2. Hydroxyl radicals are then generated by a Fenton type reaction and they can react with various wood compounds, including lignin. In this work we study the effect of CDH on a non-phenolic lignin model compound (3,4-dimethoxyphenyl glycol). The results indicate that CDH can affect lignins in three important ways. (1) It breaks beta-ethers; (2) it demethoxylates aromatic structures in lignins; (3) it introduces hydroxyl groups in non-phenolic lignins. The gamma-irradiated model compound gave a similar pattern of products as the CDH treated model compound? when the samples were analyzed by HPLC, suggesting that hydroxyl radicals are the active component of the CDH system.
Place, publisher, year, edition, pages
2000. Vol. 1480, no 02-jan, 83-91 p.
cellobiose dehydrogenase, hydroxyl radical, lignin degrading enzyme, lignin, wood biodegradation, white-rot fungus, sporotrichum-pulverulentum, manganese peroxidase, coniophora-puteana, synthetic lignin, model compounds, oxidase, degradation, laccase, oxidation
IdentifiersURN: urn:nbn:se:kth:diva-19932DOI: 10.1016/S0167-4838(00)00096-0ISI: 000088459000010OAI: oai:DiVA.org:kth-19932DiVA: diva2:338624
QC 201005252010-08-102010-08-10Bibliographically approved