【作者】 秦星； 苏小运； 罗会颖； 余洪波； 张晓昱； 马锐； 姚斌； 马富英；

【机构】 中国农业科学院饲料研究所；

【摘要】 The white rot fungus Irpex lacteusis one of the most potent fungi in degradation of lignocellulose and xenobiotics;however,the biological mechanism involved is poorly understood.Thus,I.lacteus CD2 is selected to elucidate the unique strategy of lignocellulose conversionby biochemical,genomic,and transcriptomic analyses./.lacteus CD2 evolves an unusual strategy in degrading lignocellulose in that it preferentially degrades lignin and xylan at the early stage,followed by cellulose at the advanced stage.Moreover,I.lacteus CD2 achieves the efficient removal of lignin by manganese peroxidases rather than lignin peroxidases and dye-decolorizing peroxidases coupled with hydrogen peroxide-generating oxidases including glyoxal oxidases,aryl alcohol oxidases and alcohol oxidases.Also hydroxyl radical based on Fenton reaction and carboxylate derived radicals generated from chelated manganese(III) ions-mediated carboxylic acid oxidation play important roles in non-phenolic lignin degradation.Besides,the metabolism of low molecular weight compounds also contributes to the efficient depolymerization of lignin.Furthermore,carbohydrate active enzymes related to polysaccharides degradation gradually increased over time.Our results suggest that wood decayby I.lacteus CD2 involves sequentially up-regulated expression of enzymes associated with lignocellulose degradation.更多还原

【Abstract】 The white rot fungus Irpex lacteusis one of the most potent fungi in degradation of lignocellulose and xenobiotics;however,the biological mechanism involved is poorly understood.Thus,I.lacteus CD2 is selected to elucidate the unique strategy of lignocellulose conversionby biochemical,genomic,and transcriptomic analyses./.lacteus CD2 evolves an unusual strategy in degrading lignocellulose in that it preferentially degrades lignin and xylan at the early stage,followed by cellulose at the advanced stage.Moreover,I.lacteus CD2 achieves the efficient removal of lignin by manganese peroxidases rather than lignin peroxidases and dye-decolorizing peroxidases coupled with hydrogen peroxide-generating oxidases including glyoxal oxidases,aryl alcohol oxidases and alcohol oxidases.Also hydroxyl radical based on Fenton reaction and carboxylate derived radicals generated from chelated manganese(III) ions-mediated carboxylic acid oxidation play important roles in non-phenolic lignin degradation.Besides,the metabolism of low molecular weight compounds also contributes to the efficient depolymerization of lignin.Furthermore,carbohydrate active enzymes related to polysaccharides degradation gradually increased over time.Our results suggest that wood decayby I.lacteus CD2 involves sequentially up-regulated expression of enzymes associated with lignocellulose degradation.更多还原