DEACETYLATION OF CHITIN OLIGOSACCHARIDES OF DP-2-4 BY CHITIN DEACETYLASE FROM COLLETOTRICHUM-LINDEMUTHIANUM

Chitin oligosaccharides of degree of polymerization 2-4 were deacetyla ted by purified chitin deacetylase isolated from Colletotrichum lindem uthianum to give their corresponding breakdown products after purifica tion by liquid chromatography. Data from FABMS analyses suggested that N, N', N '', N'''-tetraacetylchitotetraose and N, N', N ''-triacetylc hitotriose were converted into fully-deacetylated corresponding chitos an oligomers. Conversely, N,N'-diacetylchitobiose [(GlcNAc)(2)] was de acetylated to give a product which showed an [M + H](+) pseudomolecula r ion at m/z 383, suggesting that either of the two acetyl groups were removed. Further data from H-1 NMR analyses confirmed that the reacti on product was o-2-deoxy-beta-D-glucopyranosyl)-2-deoxy-D-glucose [Glc N-GlcNAc]. The enzymatic method has three advantageous characteristics over chemical methods: (i) it does not cause unexpected degradation o f the sugar chain, (ii) it is highly reproducible, and (iii) unique co mpounds such as GlcN-GlcNAc may be produced. (C) 1997 Elsevier Science Ltd.