Live Attenuated Bacterial Vaccine

Abstract

A live, attenuated bacterium of the genus Escherichia, Yersinia or Salmonella, that does not have a functional tRNA<SUP>5</SUP><SUB>leu</SUB>, and vaccines comprising the live, attenuated bacterium.

1 . A live, attenuated bacterium of the genus  Escherichia, Yersinia  or  Salmonella , said bacterium not having a functional tRNA 5   leu .  
     
     
         2 . The live, attenuated bacterium according to  claim 1 , said bacterium not having a functional tRNA 5   leu  as a result of a mutation in the leux gene.  
     
     
         3 . The live, attenuated bacterium according to  claim 1 , wherein said bacterium is selected from the group consisting of  E. coli, S. enterica serotype typhimurium, enteritidis, choleraesuis, dublin, typhi, gallinarum, abortusovi, abortus - equi  and  pullorum.    
     
     
         4 . The live, attenuated bacterium according to  claim 2 , wherein the mutation comprises an insertion and/or a deletion.  
     
     
         5 . The live, attenuated bacterium according to  claim 1 , wherein said bacterium carries a heterologous gene.  
     
     
         6 . The live, attenuated bacterium according to  claim 5 , wherein the heterologous gene is inserted in the leux gene.  
     
     
         7 . A vaccine for the protection of animals and humans against infection with a pathogenic bacterium or the pathogenic effects thereof, comprising the bacterium of  claim 1  and a pharmaceutically acceptable carrier.  
     
     
         8 . The vaccine according to  claim 7 , comprising an adjuvant.  
     
     
         9 . The vaccine according to  claim 7  in a freeze-dried form.  
     
     
         10 - 11 . (canceled)  
     
     
         12 . A method for protecting a susceptible human or animal from infection with a pathogenic bacterium, comprising administering an effective amount of vaccine according to  claim 7.