Novel Bacteriocins, Transport and Vector System and Method of Use Thereof

Abstract

New bacteriocins capable of inhibiting the growth of bacteria are disclosed, along with methods of obtaining secretion of proteins from lactic acid bacteria, and methods for protecting foodstuffs.

1 . A secretion vector, for providing secretion of a heterologous protein from a microbial host cell, said secretion vector comprising:
 a first polynucleotide encoding a heterologous protein;   a second polynucleotide encoding a bacteriocin processing peptide operable in said host cell, operably linked to said polynucleotide encoding said heterologous protein; and   a promoter operable in said host cell, operably linked to said polynucleotide encoding said heterologous protein.   
     
     
         2 . The secretion vector of  claim 1 , wherein said bacteriocin processing peptide comprises a divergicin A processing peptide or an operable mutein thereof. 
     
     
         3 . The secretion vector of  claim 1 , wherein said first polynucleotide encodes a heterologous bacteriocin. 
     
     
         4 . The secretion vector of  claim 3 , further comprising an immunity gene which confers immunity from said heterologous bacteriocin to said host cell. 
     
     
         5 . The secretion vector of  claim 3 , wherein said vector encodes a plurality of different bacteriocins. 
     
     
         6 . The vector pCD3.4 (SEQ ID NO:14). 
     
     
         7 . A host cell transformed with the secretion vector of  claim 5 . 
     
     
         8 . A host cell transformed with a plurality of secretion vectors of  claim 5 . 
     
     
         9 . A host cell transformed with the secretion vector of  claim 5 . 
     
     
         10 . A method for obtaining secretion of a protein from a microorganism, said method comprising:
 providing a secretion vector comprising a promoter operable in said microorganism, operably linked to a polynucleotide encoding a bacteriocin processing peptide operable in said microorganism, operably linked to a polynucleotide encoding said protein;   transforming said microorganism with said secretion vector; and   culturing said transformed microorganism under conditions that induce expression and secretion.   
     
     
         11 . The method of  claim 10 , wherein said bacteriocin processing peptide comprises a divergicin A processing peptide. 
     
     
         12 . A secretion vector for providing secretion of a heterologous protein from a lactic acid host, said secretion vector comprising
 a first polynucleotide encoding a heterologous protein;   a second polynucleotide encoding a processing peptide suitable for expressing said heterologous protein and operably linked to said first polynucleotide; and   a promoter operable in said host cell and operably linked to said first polynucleotide.   
     
     
         13 . The secretion vector of  claim 12  wherein the processing peptide is a signal peptide. 
     
     
         14 . The secretion vector of  claim 13  wherein the signal peptide is from divergicin A. 
     
     
         15 . A method of expressing a heterologous protein by applying an expression vector as defined in  claim 12 .