Live attenuated bacterial vaccine to reduce or inhibit carriage and shedding of enterohemorrhagic
The invention provides live, attenuated enterohemorrhagic Escherichia coli (EHEC) bacteria in which the Shiga toxin coding sequences are deleted to abolish Shiga toxin production and one or more of the nucleotide sequences for the bacterial adhesin protein intimin, the locus of enterocyte effacement encoded regulator, and the translocated intimin receptor are mutated to inactivate the activity of the encoded protein(s). This live, attenuated E. coli bacteria is used in a vaccine for reducing or inhibiting carriage and shedding of EHEC in cattle.
1. An isolated, live attenuated, double mutant of enterohemorrhagic Escherichia coli (EHEC) O157:H7, E. coli O26, or E. coli O111 in which the Shiga toxin coding sequence is deleted to abolish its Shiga toxin production and the nucleotide sequence coding for its bacterial adhesion protein, intimin or Eae, is mutated by deletion of the C-terminal Tir-binding domain to eliminate intimin's Tir binding activity while retaining rest of the intimin that comprises the intimin's immunodominant regions.
2. The live attenuated double mutant of claim 1 , which contains no antibiotic resistance marker.
3. The live attenuated double mutant of claim 1 comprising a pharmaceutically acceptable carrier.
4. The live attenuated double mutant of claim 1 comprising an adjuvant.
5. The live attenuated double mutant of claim 2 comprising a pharmaceutically acceptable carrier.
6. The live attenuated double mutant of claim 2 comprising an adjuvant.