received by the International Bureau on 09 December 2019 (09.12.2019)

1. A vaccine composition comprising an outer membrane protein of P. aeruginosa, wherein:

the outer membrane protein is an FpvA peptide; and

the FpvA peptide is at least one peptide selected from the group consisting of:

a peptide having a sequence consisting of SEQ ID NO: 1,

a peptide comprising a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4; and

a combination thereof.

2. The vaccine composition of claim 1, wherein the FpvA peptide comprises at least one peptide having a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and a combination thereof.

3. The vaccine composition of claim 2, wherein the FpvA peptide comprises a modification at the C-terminus.

4. The vaccine composition of claim 3, wherein the FpvA peptide further comprises a modification at the N-terminus.

5. The vaccine composition of claim 2, wherein the composition further comprises additional outer membrane proteins of P. aeruginosa.

6. The vaccine composition of claim 2, wherein the composition further comprises additional immune-stimulatory molecules.

7. The vaccine composition of claim 6, wherein the additional immune-stimulatory molecules are selected from the group consisting of carrier proteins and adjuvants.

8. The vaccine composition of claim 7, wherein the carrier protein is selected from the group consisting of keyhole limpet hemocyanin, recombinant tetanus toxoid (rTTHc) and recombinant diphtheria toxoid (CRM₁₉₇).

9. The vaccine composition of claim 7 wherein the adjuvant is a B-glucan or alum.

10. The vaccine composition of claim 9, wherein the B-glucan is curdlan.

11. The vaccine composition of claim 2, wherein the composition is administered via a mucosal delivery method or via injection.

12. The vaccine composition of claim 1, wherein the FpvA peptide comprises at least one peptide having a sequence consisting of a sequence of SEQ ID NO: 1.

13. The vaccine composition of claim 12, wherein the peptide comprises a modification at the C- terminus.

14. The vaccine composition of claim 13, wherein the peptide further comprises a modification at the N-terminus.

15. The vaccine composition of claim 12, wherein the composition further comprises additional outer membrane proteins of P. aeruginosa.

16. The vaccine composition of claim 12, wherein the composition further comprises additional immune-stimulatory molecules.

17. The vaccine composition of claim 16, wherein the additional immune-stimulatory molecules are selected from the group consisting of carrier proteins and adjuvants.

18. The vaccine composition of claim 17, wherein the carrier protein is selected from the group consisting of keyhole limpet hemocyanin, recombinant tetanus toxoid (rTTHc) and recombinant diphtheria toxoid (CRM₁₉₇).

19. The vaccine composition of claim 17, wherein the adjuvant is a B-glucan or alum.

20. The vaccine composition of claim 19, wherein the B-glucan is curdlan.

21. The vaccine composition of claim 12, wherein the composition is administered via a mucosal delivery method or via injection.

22. A method of preventing an infection comprising administering a vaccine composition comprising an outer membrane protein of P. aeruginosa ,

wherein the outer membrane protein is an FpvA peptide; and

the FpvA peptide is at least one peptide selected from the group consisting of: a peptide having a sequence consisting of a sequence of SEQ ID NO: 1, a peptide having a sequence comprising a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4; and

a combination thereof..

23. The method of claim 22, wherein the FpvA peptide comprises a sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and a combination thereof.

24. The method of claim 22, wherein the composition further comprises additional immune- stimulatory molecules.

25. The method of claim 24, wherein the additional immune-stimulatory molecules are selected from the group consisting of carrier proteins and adjuvants.

26. The method of claim 25, wherein the carrier protein is selected from the group consisting of keyhole limpet hemocyanin, recombinant tetanus toxoid (rTTHc) and recombinant diphtheria toxoid (CRM₁₉₇).

27. The method of claim 25, wherein the adjuvant is a B-glucan or alum.

28. The method of claim 27, wherein the B-glucan is curdlan.

29. The method of claim 22, wherein the vaccine composition generates antibodies that induce iron starvation in low iron conditions.

30. The method of claim 22, wherein the vaccine composition triggers the production of opsonic antibodies.