Engineered type IV pilin of Clostridium difficile

An immunogenic composition comprising an isolated polypeptide comprising i) a C. difficile type IV pilin or an antigenic fragment or variant thereof, and ii) an affinity tag sequence to facilitate purification, wherein the antigenic fragment or variant thereof comprises a polypeptide sequence that has at least 90% sequence identity to a polypeptide sequence selected from the group consisting of:

• a. amino acids 35-173 of SEQ ID NO:2;
• b. amino acids 35-173 of SEQ ID NO:6;
• c. amino acids 35-173 of SEQ ID NO:10;
• d. amino acids 35-171 of SEQ ID NO:14;
• e. amino acids 35-170 of SEQ ID NO:18;
• f. amino acids 34-119 of SEQ ID NO:22;
• g. amino acids 31-116 of SEQ ID NO:26;
• h. amino acids 32-164 of SEQ ID NO:30;
• i. amino acids 32-164 of SEQ ID NO:34;
• j. amino acids 32-162 of SEQ ID NO:38;
• k. amino acids 36-272 of SEQ ID NO:42;
• l. SEQ ID NO:2;
• m. SEQ ID NO:6;
• n. SEQ ID NO:10;
• o. SEQ ID NO:14;
• p. SEQ ID NO:18;
• q. SEQ ID NO:22;
• r. SEQ ID NO:26;
• s. SEQ ID NO:30;
• t. SEQ ID NO:34;
• and
• u. SEQ ID NO:38.