Effects of hemicelluloses on dehydrogenative polymerization of monolignols with cationic cell wall-bound peroxidase

To elucidate the influence of polysaccharides on hardwood lignification, dehydrogenative polymerization of monolignols, coniferyl alcohol (CA) and sinapyl alcohol (SA), was attempted with recombinant cationic cell wall-bound peroxidase (rCWPO-C) and horseradish peroxidase (HRP) in measurement cells of a quartz crystal mi-crobalance with dissipation (QCM-D). Hardwood cellulose nanofibers were anchored; hemicelluloses, xylan, partially acetylated xylan (AcXY), galactoglucomannan, and xyloglucan, and the enzymes were subsequently adsorbed onto the QCM-D sensor surface, enabling fabrication of artificial polysaccharide matrices. The largest amount of rCWPO-C is found to be adsorbed onto AcXY among all the polysaccharides, which affords the largest amount and size of spherical dehydrogenation polymers (DHPs) from both CA and SA. In contrast, no DHP and a small amount of DHPs are formed from SA and CA, respectively, by HRP catalysis in all of the polysaccharide matrices. This study demonstrates important functions of a real tree-derived peroxidase, rCWPO-C, and AcXY for hardwood lignification.

Automated summary

The influence of polysaccharides on hardwood lignification was investigated using recombinant cationic cell wall-bound peroxidase (rCWPO-C) and partially acetylated xylan (AcXY). The results showed that AcXY plays a crucial role in the formation of spherical dehydrogenation polymers (DHPs) from coniferyl alcohol and sinapyl alcohol, highlighting the important functions of rCWPO-C and AcXY in hardwood lignification.