Rhamnosyl-tranferase gene and uses thereof

Abstract

An isolated polynucleotide comprising a nucleotide sequence encoding a polypeptide having a flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase catalytic activity and its uses.

1 - 47 . (canceled)  
     
     
         48 . A commercial process of producing neohesperidin comprising the steps of: 
 (a) obtaining hesperidin;    (b) treating said hesperidin with a hesperidinase, thereby obtaining hesperetin-7-glucoside; and    (c) treating said hesperetin-7-glucoside with a flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase in the presence of activated rhamnose, thereby obtaining neohesperidin.    
     
     
         49 . The commercial process of  claim 48 , wherein said activated rhamnose is selected from the group consisting of UDP-rhamnose or dTDP-rhamnose.  
     
     
         50 . The commercial process of  claim 48 , wherein said hesperidinase is immobilized on a solid support, whereas said hesperidin is treated with said hesperidinase while passing over said solid support.  
     
     
         51 . The commercial process of  claim 48 , wherein said treatment of hesperetin-7-glucoside with a flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase in presence of activated rhamnose of step (c) is effected in vivo by a cell genetically modified to overexpress said flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase, which said cell is producing activated rhamnose and is capable of intake of said hesperetin-7-glucoside.  
     
     
         52 . The commercial process of  claim 51 , further comprising the step of extracting said neohesperidin from said cell.  
     
     
         53 . A commercial process of producing neohesperidin dihydrochalcone comprising the steps of: 
 (a) obtaining hesperidin;    (b) treating said hesperidin with a hesperidinase, thereby obtaining hesperetin-7-glucoside;    (c) treating said hesperetin-7-glucoside with a flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase in the presence of activated rhamnose, thereby obtaining neohesperidin;    (d) treating said neohesperidin with an alkali, thereby obtaining neohesperidin chalcone; and    (e) reducing said neohesperidin chalcone, thereby obtaining neohesperidin dihydrochalcone    
     
     
         54 . The commercial process of  claim 53 , wherein said activated rhamnose is selected from the group consisting of UDP-rhamnose or dTDP-rhamnose.  
     
     
         55 . The commercial process of  claim 53 , wherein said hesperidinase is immobilized on a solid support, whereas said hesperidin is treated with said hesperidinase while passing over said solid support.  
     
     
         56 . The commercial process of  claim 53 , wherein said treatment of hesperetin-7-glucoside with a flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase in presence of activated rhamnose of step (c) is effected in vivo by a cell genetically modified to overexpress said flavanone-7-O-glucoside-2″-O-rhamnosyl-transferase, which said cell is producing activated rhamnose and is capable of intake of said hesperetin-7-glucoside.  
     
     
         57 . The commercial process of  claim 56 , further comprising the step of extracting said neohesperidin from said cell prior to treating said neohesperidin with said alkali.  
     
     
         58 .- 83 . (canceled)