Tryparedoxin, expression plasmid, process of preparation, method of use, test kit and pharmaceutical composition

Abstract

The present invention provides novel enzymes, tryparedoxins, their isolation from Crithidia fasciculata, a method for the production thereof in genetically transformed bacteria, and their use as molecular targets for the discovery of trypanocidal drugs

1 - 28 . (canceled)  
     
     
         29 . An isolated tryparedoxin (TXN) protein, said TXN protein having an activity which transfers reductive equivalents of trypanothione (T(SH) 2 ) to a peroxiredoxin, said TXN protein having a molecular weight of between 15 kDa to 19 kDa as determined by mass spectrometry, and said protein having a WCPPC motif.  
     
     
         30 . The protein of  claim 29 , wherein said TXN protein is prepared by genetic engineering.  
     
     
         31 . The protein of  claim 30 , wherein said TXN protein is prepared by expression of a plasmid comprising a nucleic acid molecule encoding said protein.  
     
     
         32 . The protein of  claim 29 , wherein said TXN protein is prepared or isolated from a species of the family Trypanosomatidae.  
     
     
         33 . The protein of  claim 29 , wherein said TXN protein catalyzes the reduction of a protein disulfide by T(SH) 2 .  
     
     
         34 . An isolated polypeptide comprising an amino acid sequence that is at least 70 percent homologous to the amino acid sequence of SEQ ID NO: 4 or 6, wherein the polypeptide has tryparedoxin (TXN) activity.  
     
     
         35 . The polypeptide of  claim 34  comprising the amino acid sequence set forth in SEQ ID NO: 4.  
     
     
         36 . The polypeptide of  claim 34  comprising the amino acid sequence set forth in SEQ ID NO: 6.  
     
     
         37 . The polypeptide of  claim 34  comprising a portion of the amino acid sequence of SEQ ID NO: 4, wherein said portion retains a WCPPC motif and retains TXN activity.  
     
     
         38 . The polypeptide of  claim 34  comprising a portion of the amino acid sequence of SEQ ID NO: 6, wherein said portion retains a WCPPC motif and retains TXN activity.  
     
     
         39 . The polypeptide of  claim 34  comprising at least 120 amino acids of SEQ ID NO: 6.  
     
     
         40 . The polypeptide of any of claims  34 - 39 , wherein said polypeptide is prepared or isolated from a species of the family Trypanosomatidae.  
     
     
         41 . The polypeptide of any of claims  34 - 39 , wherein said polypeptide catalyzes the reduction of a protein disulfide by T(SH) 2 .  
     
     
         42 . The polypeptide of  claim 31  encoded by the nucleic acid molecule of SEQ ID NO: 5.  
     
     
         43 . The polypeptide of  claim 31  encoded by the nucleic acid molecule of SEQ ID NO: 7.