The importance of phenol oxidase activity in lignin degradation by the white-rot fungusSporotrichum pulverulentum

✍ Scribed by Paul Ander; Karl-Erik Eriksson

• Publisher: Springer
• Year: 1976
• Tongue: English
• Weight: 893 KB
• Volume: 109
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00425105

✦ Synopsis

The lignin degradation abilities of wildtype, a phenol oxidase-less mutant and a phenol oxidasepositive revertant of Sporotrichum pulverulentum were compared to determine if phenol oxidase activity is necessary for lignin degradation by white-rot fungi. The phenol oxidase-less mutant was unable to degrade kraft lignin or wood. The phenol oxidase-positive revertant, however, regained the ability of the wildtype to degrade kraft lignin and all of the major components of wood. It was found that kraft lignin and lignin-related phenols decreased cellulase and xylanase production by the phenol oxidase-less mutant. Addition of highly purified laccase increased the production of endo-l,4-fl-glucanase in the phenol oxidase-less mutant in the presence of vanillic acid and kraft lignin. After addition of laccase to kraft lignin agar plates, the phenol oxidase-less mutant could degrade kraft lignin.

It is proposed that phenol oxidase function in regulating the production of both lignin-and polysaccharide-degrading enzymes by oxidation of lignin and lignin-related phenols when S.pulverulentum is growing on wood.