Lytic polysaccharide monooxygenases from Myceliophthora thermophila C1 differ in substrate preference and reducing agent specificity

Table 1 Oxidation of various polysaccharide substrates by MtLPMO9A, MtLPMO9B and MtLPMO9C

Substrate	Occurrence of oxidation (upon addition of 1 mM ascorbic acid)
	MtLPMO9A^a		MtLPMO9B		MtLPMO9C		No enzyme
	GlcOS ^{# * b}_n	XOS ^{# * c}_n	GlcOS ^#_n	XOS ^#_n	GlcOS_n*	XOS_n*	GlcOS_n*	XOS_n*
Cellulose
RAC^d	+	+	+	–	+	–	–	–
Hemicellulose
Glucan
Xyloglucan^e	+	–	–	–	+	–	–	–
β-Glucan barley^e	+	–	–	–	–	–	–	–
β-Glucan oat spelt^e	+	–	–	–	+	–	–	–
Xylan
OSX^f	–	–	–	–	–	–	–	–
BiWX^f	–	–	–	–	–	–	–	–
WAX^f	–	–	–	–	–	–	–	–
Oligosaccharides
Gluco-oligosaccharides^g	–	–	–	–	–	–	–	–
Xylo-oligosaccharides^g	–	–	–	–	–	–	–	–
RAC/Hemicellulose combination
RAC + BiWX	+	+	+	–	+	–	–	–
RAC + OSX	+	+	+	–	+	–	–	–
RAC + WAX	+	–	+	–	+	–	–	–

Oligosaccharides released and not released refers to + and −, respectively
^aData from Frommhagen et al. [ 2 ]
^bGluco-oligosaccharides oxidized at the C1 (GlcOS ^#_n ) or C4 position (GlcOS_n*)
^cXylo-oligosaccharides oxidized at the C1 (XOS ^#_n ) or C4 position (XOS_n*)
^dRegenerated amorphous cellulose (RAC)
^eXyloglucan from tamarind seed, β-(1 → 3, 1 → 4)-glucan from barley and β-(1 → 3, 1 → 4)-glucan from oat spelt
^fOat spelt xylan (OSX), birchwood xylan (BiWX), wheat arabinoxylan (WAX)
^gβ-(1 → 4)-linked gluco- and xylo-oligosaccharides, degree of polymerization 2–5

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