Immunogenic proteins against clostridium difficile

1. An immunogenic protein comprising:

i) a glucosyltransferase domain of Clostridium difficile toxin TcdB;

ii) a cysteine proteinase domain of Clostridium difficile toxin TcdB; and

iii) a receptor binding domain of Clostridium difficile toxin TcdA,

wherein the cysteine proteinase domain of Clostridium difficile toxin TcdB comprises a C698A amino acid substitution when compared to SEQ ID NO.: 8, and wherein the immunogenic protein lacks a transmembrane domain.

2. The immunogenic protein of claim 1 , wherein the immunogenic protein further comprises a receptor binding domain of Clostridium difficile toxin TcdB.

3. The immunogenic protein of claim 1 , wherein the immunogenic protein further comprises Salmonella typhimurium flagellin.

4. The immunogenic protein of claim 1 , wherein the immunogenic protein further comprises a receptor binding domain of Clostridium difficile toxin TcdB and Salmonella typhimurium flagellin.

5. The immunogenic protein of claim 1 , wherein the glucosyltransferase domain of Clostridium difficile toxin TcdB comprises a W102A amino acid substitution and a D288N amino acid substitution when compared to SEQ ID NO.: 8.

6. A pharmaceutical composition comprising the immunogenic protein of claim 1 and a pharmaceutically acceptable carrier.

7. A method of treating a Clostridium difficile bacterial infection in a subject in need thereof, the method comprising administering to the subject the pharmaceutical composition of claim 6 .

8. An immunogenic protein comprising:

i) a glucosyltransferase domain (GT) of Clostridium difficile toxin TcdB;

ii) a cysteine proteinase domain (CPD) of Clostridium difficile toxin TcdB;

iii) a receptor binding domain (RBD) of Clostridium difficile toxin TcdB; and

iv) a receptor binding domain (RBD) of Clostridium difficile toxin TcdA;

wherein the GT of Clostridium difficile toxin TcdB comprises a W102A amino acid substitution and a D288N amino acid substitution when compared to SEQ ID NO.: 8 and the CPD of Clostridium difficile toxin TcdB comprises a C698A amino acid substitution when compared to SEQ ID NO.: 8, and wherein the immunogenic protein lacks a transmembrane domain.

9. The immunogenic protein of claim 8 , wherein the immunogenic protein comprises the amino acid sequence of SEQ ID NO.: 5.

10. The immunogenic protein of claim 8 , wherein the immunogenic protein further comprises flagellin of Salmonella typhimurium (sFliC).

11. The immunogenic protein of claim 10 , wherein the immunogenic protein comprises the amino acid sequence of SEQ ID NO.: 6.

12. A pharmaceutical composition comprising the immunogenic protein of claim 8 and a pharmaceutically acceptable carrier.

13. A method of treating a Clostridium difficile bacterial infection in a subject in need thereof, the method comprising administering to the subject the pharmaceutical composition of claim 12 .

14. An immunogenic protein comprising:

i) a glucosyltransferase domain (GT) of Clostridium difficile toxin TcdB;

ii) a cysteine proteinase domain (CPD) of Clostridium difficile toxin TcdB;

iii) a receptor binding domain (RBD) of Clostridium difficile toxin TcdA; and

iv) flagellin of Salmonella typhimurium (sFliC);

wherein the GT of Clostridium difficile toxin TcdB comprises a W102A amino acid substitution and a D288N amino acid substitution when compared to SEQ ID NO.: 8 and the CPD of Clostridium difficile toxin TcdB comprises a C698A amino acid substitution when compared to SEQ ID NO.: 8, and wherein the immunogenic protein lacks a transmembrane domain.

15. The immunogenic protein of claim 14 , wherein the immunogenic protein comprises the amino acid sequence of SEQ ID NO.: 7.

16. A pharmaceutical composition comprising the immunogenic protein of claim 14 and a pharmaceutically acceptable carrier.

17. A method of treating a Clostridium difficile bacterial infection in a subject in need thereof, the method comprising administering to the subject the pharmaceutical composition of claim 16 .

18. The immunogenic protein of claim 1 , wherein the glucosyltransferase domain of Clostridium difficile toxin TcdB is positioned immediately upstream of the cysteine proteinase domain of Clostridium difficile toxin TcdB, wherein the amino acid sequence of the linked glucosyltransferase domain of Clostridium difficile toxin TcdB and the cysteine proteinase domain of Clostridium difficile toxin TcdB is set forth in SEQ ID NO.: 8; and wherein the receptor binding domain of Clostridium difficile toxin TcdA comprises the amino acid sequence of SEQ ID NO.: 9.

19. The immunogenic protein of claim 8 , wherein the glucosyltransferase domain of Clostridium difficile toxin TcdB is positioned immediately upstream of the cysteine proteinase domain of Clostridium difficile toxin TcdB, wherein the amino acid sequence of the linked glucosyltransferase domain of Clostridium difficile toxin TcdB and the cysteine proteinase domain of Clostridium difficile toxin TcdB is set forth in SEQ ID NO.: 8; wherein the receptor binding domain of Clostridium difficile toxin TcdA comprises the amino acid sequence of SEQ ID NO.: 9; and wherein the receptor binding domain of Clostridium difficile toxin TcdB comprises the amino acid sequence of SEQ ID NO.: 10.

20. The immunogenic protein of claim 14 , wherein the glucosyltransferase domain of Clostridium difficile toxin TcdB is positioned immediately upstream of the cysteine proteinase domain of Clostridium difficile toxin TcdB, wherein the amino acid sequence of the linked glucosyltransferase domain of Clostridium difficile toxin TcdB and the cysteine proteinase domain of Clostridium difficile toxin TcdB is set forth in SEQ ID NO.: 8; wherein the receptor binding domain of Clostridium difficile toxin TcdA comprises the amino acid sequence of SEQ ID NO.: 9; and wherein the flagellin of Salmonella typhimurium comprises the amino acid sequence of SEQ ID NO.: 11.