Cellobiose Dehydrogenase：Inhibition of Polymerization
of Phenolic
Compounds and Enhancing Lignin Degradation by Ligninases
FANG Jing,LIU Wen and GAO Pei-Ji
( The State Key Laboratory of Microbial Technology,Shandong
University,Jinan 250100,China )
Abstract The kinetic behavior of
cellobiose dehydrogenase (CDH) was investigated by steady-state initial
velocity studies. Variation in the concentration of one substrate led to
changes in Km and Vmax of the other substrate. The
results were consistent with a ping-pong mechanism. In the presence of
cellobiose,CDH could reduce many oxidized products catalyzed by soybean hull
peroxidase (SHP). The oxidation product of 1-hydroxybenzotriazole (HBT)
catalyzed by SHP inactivated the enzyme itself；however,CDH could prevent SHP
from inactivation by reducing the oxidation product of HBT. CDH could also
inhibit the polymerization of phenolic compounds catalyzed by SHP. It was found
that the addition of CDH could enhance kraft pulp lignin degradation by ligninases.
Key Words Cellobiose dehydrogenase；soybean hull peroxidase；redox interaction；ligninases；lignin degradation
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