Sulfated fucoglucuronomannan

Abstract

An enzyme which decomposes a sulfated fucoglucuronomannan and is useful in the field of glycotechnology; a process for producing the enzyme; a fucoidan fraction reduced in the number of the kinds of molecules and useful as a reagent in glycotechnology; a sulfated fucoglucuronomannan oligosaccharide; and processes for producing the fraction and oligosaccharide.

1 . A sulfated fucoglucuronomannan having the following chemical and physical properties, or a salt thereof: 
 (1) containing fucose, mannose and glucuronic acid as constituting saccharides; and    (2) converted into a smaller molecule by the action of the sulfated fucoglucuronomannan lyase to generate at least a compound of general formula (II):                          wherein R is H or SO 3 H.    
     
     
         2 . A sulfated fucoglucuronomannan lyase having the following chemical and physical properties: 
 (I) capable of acting on a sulfated fucoglucuronomannan defined by  claim 1  and cleaving an α-D-mannosyl bond eliminatively to generate an oligosaccharide having an unsaturated glucuronate group;    (II) having an optimal pH of about 6.5 to 8.0; and    (III) having an optimal temperature of about 30 to 40° C.    
     
     
         3 . A method for producing the sulfated fucoglucuronomannan lyase defined by  claim 2 , the method comprising: 
 culturing a bacterium of the genus  Fucophilus  that is capable of producing the sulfated fucoglucuronomannan lyase defined by  claim 2;  and    collecting said enzyme from the culture.    
     
     
         4 . A method for producing a sulfated fucoglucuronomannan oligosaccharide of general formula (I) or (II), or a salt thereof,  
       
         
           
           
               
               
           
         
       
       wherein R is H or SO 3 H,  
       
         
           
           
               
               
           
         
       
       wherein R is H or SO 3 H, 
 the method comprising allowing the sulfated fucoglucuronomannan lyase defined by  claim 2  to act on a sulfated fucoglucuronomannan-containing fraction derived from an alga of the order Fucales.  
 
     
     
         5 . A fucoidan fraction which is obtainable according to a method comprising removing a sulfated fucoglucuronomannan converted into a smaller molecule by allowing the sulfated fucoglucuronomannan lyase defined by  claim 2  to act on a sulfated polysaccharide mixture fraction derived from a brown alga.  
     
     
         6 . A method for producing a fucoidan fraction, the method comprising: 
 allowing the sulfated fucoglucuronomannan lyase defined by  claim 2  to act on a sulfated polysaccharide mixture fraction derived from a brown alga; and    collecting a fucoidan fraction.    
     
     
         7 . A reagent for glycotechnology which contains the sulfated fucoglucuronomannan lyase defined by  claim 2.