**2.7 Additional effect of Pb-LPMO during the hydrolysis of crystalline chitin by Pb-ChiA**

We incubated 1 μM Pb-ChiA and 1.0 mM ascorbic acid with or without 3 μM Pb-LPMO in 20 mM acetate buffer (pH 5.0) with α-chitin at 37°C for 24 h. The reaction mixture was then boiled for 10 min to terminate the enzyme reaction. The samples were mixed with the same volume of acetonitrile. The resultant solution was applied onto the same column and conditions mentioned in Section 2.4. In this experiment, we investigated the total concentration of GlcNAc, (GlcNAc)2, and total sugars (GlcNAc). The concentration of (GlcNAc)2 in total sugars was calculated as twice the concentration of GlcNAc.
