Novel aldolase and production process of substituted alpha-keto acids

Abstract

4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutarate, which is useful as an intermediate in the synthesis of monatin, may be synthesized from indole pyruvic acid and pyruvic acid (and/or oxaloacetic acid) by using a novel aldolase derived from the genus Pseudomonas, Erwinia, Flavobacterium, or Xanthomonas.

1 .- 24 . (canceled) 
     
     
         25 . A process of producing monatin represented by formula (5) 
       
         
           
           
               
               
           
         
       
       comprising:
 reacting indole pyruvic acid with oxaloacetic acid or pyruvic acid in the presence of a protein having aldolase activity to obtain 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutarate represented by formula (4) 
 
       
         
           
           
               
               
           
         
         and converting said 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutarate represented by formula (4) to monatin. 
       
     
     
         26 . The process of  claim 25 , wherein said protein having aldolase activity is comprised in a culture comprising microbial cells. 
     
     
         27 . The process of  claim 25 , wherein said protein having aldolase activity is comprised in microbial cells. 
     
     
         28 . The process of  claim 25 , wherein said protein having aldolase activity is comprised in a culture medium in which microbial cells have been removed. 
     
     
         29 . The process of  claim 25 , wherein said protein having aldolase activity is comprised in a treated microbial cell product that have been disrupted or lysed. 
     
     
         30 . The process of  claim 25 , wherein said protein having aldolase activity is in a purified form.