Novel synthetic genes for plant gums

Abstract

A new approach in the field of plant gums is described which presents a new solution to the production of hydroxyproline(Hyp)-rich glycoproteins (HRGPs), repetitive proline-rich proteins (RPRPs) and arabino-galactan proteins (AGPs). The expression of synthetic genes designed from repetitive peptide sequences of such glycoproteins, including the peptide sequences of gum arabic glycoprotein (GAGP), is taught in host cells, including plant host cells.

1 . A fusion protein comprising a non-gum arabic protein or glycoprotein sequence and at least four amino acids of the amino acid sequence selected from the group consisting of SEQ ID NO:1 or SEQ ID NO:2.  
     
     
         2 . The fusion protein of  claim 1 , wherein said non-gum arabic sequence is a green fluorescent protein amino acid sequence.  
     
     
         3 . A method for producing at least a portion of a plant gum glycoprotein, comprising: 
 a) providing; 
 i) a recombinant expression vector comprising a polynucleotide sequence encoding at least four amino acids of a polypeptide selected from the group consisting of SEQ ID NO:1 and SEQ ID NO:2, wherein said sequence contains one amino acid substitution; and  
 ii) a host cell; and  
   b) introducing said vector into said host cell under conditions suitable for the expression of said polypeptide.    
     
     
         4 . The method of  claim 3 , wherein said host cell is growing in culture.  
     
     
         5 . The method of  claim 4 , further comprising the step of: 
 c) recovering said polypeptide from the host cell culture.    
     
     
         6 . The method of  claim 5 , wherein said host cell is a plant cell.  
     
     
         7 . The method of  claim 6 , wherein said plant cell is derived from a plant selected from the family Leguminoseae.  
     
     
         8 . The method of  claim 1 , wherein said substitution comprises a Leu or Hyp for Gly.  
     
     
         9 . The method of  claim 1 , wherein said substitution comprises a Leu for Hyp.  
     
     
         10 . The method of  claim 1 , wherein said substitution comprises an Ala for a Hyp.