Gene encoding glycosyltransferase and its uses

Abstract

This invention relates to glycosyltransferase, genes encoding glycosyltransferase, recombinant vectors having such a gene, host cells transformed with such a recombinant vector, and uses thereof. This invention makes it possible to glycosylate indolopyrrolocarbazole derivatives conveniently and economically.

We claim:  
     
       1. Purified or isolated gylcogyltransferase  glycosyltransferase having the amino acid sequence represented by SEQ ID NO:1. 
     
     
       2. Isolated DNA encoding for the glycosyltransferase having the amino acid sequence as set forth in SEQ ID NO:1. 
     
     
       3. Isolated DNA having the base sequence represented by SEQ ID NO:2. 
     
     
       4. Isolated DNA encoding a glycosyltransferase which can convert a compound of the general formula (I)                    
       wherein each of X 1  and X 2  is a hydrogen atom, a halogen atom, an amino group, a mono(lower alkyl)amino group, a di(lower alkyl)amino group, a hydroxyl group, a lower alkoxy group, an aralkoxy group, a carboxyl group, a lower alkoxycarbonyl group, a lower alkanoyloxy group or a lower alkyl group; and R is a hydrogen atom, an amino groups  group, a formylamino group, a lower alkanoylamino group, a mono (lower alkyl)amino.  group, a di(lower alkyl)amino group, a hydroxyl group, a lower alkoxy group, an aralkoxy group, an aralkyl group or a lower alkyl group,  
       to a compound of the general formula (II)                    
       wherein X 1 , X 2  and R have the same meanings as above,  
       said DNA having the base sequence represented by SEQ ID NO:2.  
     
     
       5. Isolated DNA according to claim  4  having the same base pairs sequence as DNA from a microorganism belonging to the genus Saccharothrix. 
     
     
       6. Isolated DNA according to claim  5  wherein the microorganism belonging to the genus Saccharothrix is Saccharothrix aerocolonigenes ATCC39243 strain. 
     
     
       7. A recombinant plasmid DNA vector including the DNA according to any one of claims  4 ,  2  or  3 . 
     
     
       8. A procaryotic host cell transformed with the recombinant vector according to claim  7  in a manner allowing the host cell to express said glycosyltransferase. 
     
     
       9. A transformed host cell obtained by transforming a bacterium producing a compound BE-13973C of the formula:                    
       with a recombinant vector according to claim  7 . 
     
     
       10. A transformed host cell obtained by transforming Streptomyces mobaraensis having the ability to produce the compound BE-13973C of the formula:                    
       with a recombinant vector according to claim  7 . 
     
     
       11. A process for the preparation of glycosyltransferase which comprises culturing a transformed host cell according to claim  8  to form and accumulate glycosyltransferase in the culture, and recovering glycosyltransferase from the culture. 
     
     
       12. A process for producing a compound of general formula (II)                    
       wherein each of X 1  and X 2  is a hydrogen atom, a halogen atom, an amino group, a mono(lower alkyl)amino group, a di(lower alkyl)amino group, a hydroxyl group, a lower alkoxy group, an aralkoxy group, a carboxyl group, a lower alkoxycarbonyl group, a lower alkanoyloxy group or a lower alkyl group; and R is a hydrogen atom, an amino group, a formylamino group, a lower alkanoylamino group, a mono(lower alkyl)amino group, a di(lower alkyl)amino group, a hydroxyl group, a lower alkoxy group, an aralkoxy group, an aralkyl group or a lower alkyl group,  
       which comprises culturing a transformed host cell as set forth in claim  8  in the presence of an indolopyrrolocarbazole derivative of the general formula (I)                    
       wherein X 1 , X 2  and R have the same meanings as above, and recovering a compound of the general formula (II) from the resulting culture.  
     
     
       13. A process according to claim  12  wherein X 1  and X 2  are hydroxyl groups and R is a hydrogen atom, an amino group or a lower alkyl group. 
     
     
       14. A process for producing a compound of formula (III)                    
       which comprises culturing a host cell as claimed in claim  9 , and recovering the compound of the formula (III) from the resulting culture.  
     
     
       15. The process of claim  14  which comprises culturing a host cell which is transformed host cell obtained by transforming Streptomyces mobaraensis having the ability to produce the compound BE-13973C with said recombinant vector.