Attenuated yiaO mutants of
Gram negative bacterial virulence genes are identified, thereby allowing the identification of novel anti-bacterial agents that target these virulence genes and their products, and the provision of novel gram negative bacterial mutants useful in vaccines.
1. An isolated attenuated Pasteurella multocida bacterium comprising a mutation in the polynucleotide sequence that encodes the yiaO polypeptide sequence set forth in SEQ ID NO: 77, wherein the mutation results in decreased virulence and attenuation of the bacterium.
2. The bacterium of claim 1 , wherein the mutation results in deletion of all or part of the polynucleotide sequence that encodes the yiaO polypeptide.
3. The bacterium of claim 1 , wherein the mutation results in an insertion in the polynucleotide sequence that encodes the yiaO polypeptide.
4. An immunogenic composition comprising the bacterium according to claim 1 .
5. A vaccine composition comprising the immunogenic composition according to claim 4 and a pharmaceutically acceptable carrier.
6. The vaccine composition according to claim 5 , further comprising an adjuvant.
7. An isolated attenuated Pasteurella multocida bacterium comprising a mutation in the polynucleotide sequence that encodes a yiaO polypeptide, wherein the polynucleotide sequence hybridizes to the complement of the polynucleotide sequence set forth in SEQ ID NO: 76 under stringent conditions comprising a final wash in buffer comprising 0.2×SSC/0.1% SDS, at 65° C. to 75° C.
8. The bacterium of claim 7 , wherein the mutation is in the polynucleotide sequence set forth in SEQ ID NO: 76.
9. An immunogenic composition comprising the bacterium according to claim 7 or 8 .
10. A vaccine composition comprising the immunogenic composition according to claim 9 and a pharmaceutically acceptable carrier.
11. The vaccine composition of claim 10 , further comprising an adjuvant.
12. An isolated attenuated Pasteurella multocida bacterium comprising a mutation in the polynucleotide sequence set forth in SEQ ID NO: 76 that encodes a yiaO polypeptide, wherein the mutation results in decreased virulence and attenuation of the bacterium.
13. The bacterium of claim 12 , wherein the mutation results in deletion of all or part of the polynucleotide sequence that encodes the yiaO polypeptide.
14. The bacterium of claim 12 , wherein the mutation results in an insertion in the polynucleotide sequence that encodes the yiaO polypeptide.
15. An immunogenic composition comprising a bacterium according to claim 12 .
16. A vaccine composition comprising the immunogenic composition according to claim 15 and a pharmaceutically acceptable carrier.