Methods and Compositions for Treating Phenylketonuria

Abstract

The present invention provides compositions and methods of treating hyperphenylalaninemia (e.g., phenylketonuria) in a subject in need thereof comprising administering to the subject an effective amount of a phenylalanine dehydrogenase (PheDH) polypeptide. The present invention also provides pharmaceutical formulations comprising PheDH for lowering the phenylalanine concentration in the subject (e.g., in the intestines and/or blood).

1 - 37 . (canceled) 
     
     
         38 . An isolated nucleic acid molecule comprising a nucleotide sequence encoding a phenylalanine dehydrogenase polypeptide, or a functional fragment thereof, wherein the encoded polypeptide or functional fragment has at least about 80% sequence identity to a wild-type phenylalanine dehydrogenase enzyme or functional fragment thereof from the organism  Geobacillus thermoglucosidasius.    
     
     
         39 . The isolated nucleic acid molecule of  claim 38 , wherein the nucleotide sequence is a codon-optimized sequence for expression in a host cell 
     
     
         40 . The isolated nucleic acid molecule of  claim 38 , wherein the wild-type phenylalanine dehydrogenase enzyme or functional fragment thereof from the organism  Geobacillus thermoglucosidasius  comprises the amino acid sequence of SEQ ID NO: 1. 
     
     
         41 . The isolated nucleic acid molecule of  claim 38 , wherein the encoded polypeptide or functional fragment thereof has at least about 95% sequence identity to the amino acid sequence of SEQ ID NO: 1. 
     
     
         42 . The isolated nucleic acid molecule of  claim 38 , wherein the encoded polypeptide or functional fragment thereof comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11. 
     
     
         43 . The isolated nucleic acid molecule of  claim 38 , wherein the nucleic acid molecule has been codon-optimized for expression in a bacterial cell, a yeast cell, an insect cell, or a mammalian cell. 
     
     
         44 . The isolated nucleic acid molecule of  claim 38 , wherein the nucleic acid molecule has been codon-optimized for expression in  Escherichia coli.    
     
     
         45 . The isolated nucleic acid molecule of  claim 38 , wherein the nucleotide sequence encoding the phenylalanine dehydrogenase polypeptide or functional fragment thereof comprises the nucleotide sequence of SEQ ID NO: 3. 
     
     
         46 . The isolated nucleic acid molecule of  claim 38 , wherein the nucleotide sequence encoding the phenylalanine dehydrogenase polypeptide or functional fragment thereof is operably linked to a promoter sequence. 
     
     
         47 . A plasmid comprising the isolated nucleic acid molecule of  claim 38 . 
     
     
         48 . A host cell comprising the isolated nucleic acid molecule of  claim 38 . 
     
     
         49 . The host cell of  claim 45 , wherein the host cell is  Escherichia coli, Bacillus subtilis, Pichia pastoris , or  Saccharomyces cerevisiae.