Fig. 4From: Use of chitin and chitosan to produce new chitooligosaccharides by chitinase Chit42: enzymatic activity and structural basis of protein specificityHPAEC-PAD analyses. Chromatograms of the 24 h reactions catalysed by Chit42 with chitosan QS1 (black) and colloidal chitin (blue) as substrates. Peaks: (1) GlcNAc; (2) (GlcNAc)2; (3) (GlcNAc)3; (4) (GlcNAc)4; (*) Unknown. On the right a schematic representation of polymerization degree and composition of reaction products predicted from mass spectrometry data (Additional file 1: Figure S2 and Tables S1, S2) is presented. Blue circles: GlcN. Green circles: GlcNAc. Peaks correspondence in parenthesisBack to article page