Biodegradative mechanism of the brown rot basidiomycete Gloeophyllum trabeum: evidence for an extracellular hydroquinone‐driven fenton reaction

FEBS Letters

Hammel, Kenneth E¹  Jensen, Kenneth A¹  Kerem, Zohar¹ 

[1] Institute for Microbial and Biochemical Technology, USDA Forest Products Laboratory, Madison, WI 53705, USA

关键词: Brown rot;    Wood decay;    Quinone redox cycling;    Fenton reaction;    Hydroxyl radical;    Polyethylene glycol;   

DOI  :  10.1016/S0014-5793(99)00180-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have identified key components of the extracellular oxidative system that the brown rot fungus Gloeophyllum trabeum uses to degrade a recalcitrant polymer, polyethylene glycol, via hydrogen abstraction reactions. G. trabeum produced an extracellular metabolite, 2,5-dimethoxy-1,4-benzoquinone, and reduced it to 2,5-dimethoxyhydroquinone. In the presence of 2,5-dimethoxy-1,4-benzoquinone, the fungus also reduced extracellular Fe³⁺ to Fe²⁺ and produced extracellular H₂O₂. Fe³⁺ reduction and H₂O₂ formation both resulted from a direct, non-enzymatic reaction between 2,5-dimethoxyhydroquinone and Fe³⁺. polyethylene glycol depolymerization by G. trabeum required both 2,5-dimethoxy-1,4-benzoquinone and Fe³⁺ and was completely inhibited by catalase. These results provide evidence that G. trabeum uses a hydroquinone-driven Fenton reaction to cleave polyethylene glycol. We propose that similar reactions account for the ability of G. trabeum to attack lignocellulose.

【 授权许可】

Unknown