Table 2. Parameters for Binding of CBM9.3 to Various Oligosaccharides Determined using ITC and DSF^a.

oligosaccharide	KD (×10–4 M)	ligand concentration (mM)	Ti (°C) ± SD
none	–	–	61.0 ± 0.88
maltose		10	63.0 ± 0.572
glucose	below the detection limit	10	62.3 ± 1.46
		20	63.0 ± 1.21
		100	66.7 ± 0.195
cellobiose	2.1 ± 0.25	10	65.7 ± 0.361
cellotriitol	–	10	63.0 ± 0.32
cellotriose	2.1 ± 0.14	10	68.0 ± 2.57
cellotetraose	2.4 ± 0.03	10	65.8 ± 0.091
XGO monomer mixtureb	0.83 ± 0.16	10	69.3 ± 0.78
XGO dimer mixtureb	0.98 ± 0.17	10	66.2 ± 0.701
xylobiose	2.0 ± 0.5	10	66.9 ± 0.079
xylotriose	1.9 ± 0.5	10	67.7 ± 0.221
arabinoxylo-oligosaccharide mixturec	1.6 ± 0.24	10	67.1 ± 2.17

^aFor DSF, T_i values significantly different (three standard deviations) from that of the control without a ligand are shown in bold.

^bMixture of xylogluco-oligosaccharides. Monomer refers to hepta+octa+nona-saccharides, i.e., a cellotetraose backbone with xyloside and galactoside decorations, and dimers with a cellooctaose backbone. For DSF, the heptasaccharide and the mixture sold as xyloglucan oligosaccharides (DP of ∼14) were employed.

^cMixture of 3³-α-l-arabinofuranosyl-xylotetraose and 2³-α-l-arabinofuranosylxylotetraose (for ITC) or O-AXBI mixture sold as arabinoxylan pentasaccharide (for DSF).