Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1992: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1991: ¥1,400,000 (Direct Cost: ¥1,400,000)
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Research Abstract |
The aim of this study is to develop the preparation method of the skeleton oligosaccharides of N-liked high-mannose type suger chains. First, we isolated a soil bacterium that produced alpha-1,2-mannosidase extracellulary. The enzyme was purified to homogeneity and characterized. The enzyme had a molecular weight of 380 Kda consisting of two homologous subunits of 190 Kda protein. The enzyme hydrolyzed specifically alpha-1,2-mannosidic linked oligosaccharides and D-mannose was liberated. The enzyme did not hydrolyze pNP- or methyl-alpha-mannoside. Using this mannosidase, the alpha-1,2-mannobiose and alpha-1,2-mannotriose were prepared by the reverce action of the enzyme with D-mannose as substrate. To obtainalpha-1,3-linked manno-oligosaccharides, we also found a new enzyme specific for alpha-1.3-mannan. A gram-negative bacterium, strain No. 9 was isolated from the soil samples and the organism secreted alpha-1,3-mannanase to produce alpha-1,3-manno-oligosaccharides. The enzyme was partially purified. The final product of the reaction was alpha-1,3-mannobiose. Above results indicate that alpha-1,2- and alpha-1,3-manno-oligosaccharides can be prepared enzymatically using the two bacterial enzymes.
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