(188br) Expression of SDS-Resistant Chitinase, AsChi61, Identified from Aeromonas Schubertii Using Enzymomics Analysis

Chitin is the major component of fungal cell walls, insect exoskeletons and the shells of crustaceans. Besides cellulose, chitin is the most abundant polysaccharide on the earth. Derivatives of chitin, inclusive of polysaccharides, oligosaccharides and monosaccharides, were applied for biomedicine, agriculture, environmental protection because they are biodegradable, histocmpatible and nontoxic. Recently, it attracts lots of attention since the chitin-oligosaccharides have been found to enhance the functions of immunological system in the host animals and they might display as tumoricidal agents. While, the biological activity of chitin-oligosaccharides depends on the number of polymerization. The hexamer with strong biological medical function has been demonstrated.

The bacterium with secretory chitinases, AsChi61, producing the hexameric chitin-oligosaccharides was isolated from Aeromonas schubertii in the soil of mangroves marsh of south Taiwan. The enzymes are SDS-resistant which can also be detected by activity proteomics developed. And then, the gene was cloned. Its structure and putative active sites were analyzed by molecular modeling. In this report, the recombint AsChi61 was expreesed and identified by protein techniques such as mass spectrum and peptide sequencing.