Polysaccharide and uses thereof
Provided herein is an E. coli O polysaccharide, O25B. Also provided herein are prokaryotic host cells containing enzymes (e.g., glycosyltransferases) used in O25B production. The host cells provided herein produce O25B bioconjugates, wherein said bioconjugates contain O25B linked to a carrier protein. Further provided herein are compositions, e.g., pharmaceutical compositions, including O25B and/or bioconjugates containing O25B. Such compositions can be used as vaccines against infection with ExPEC, and may further include one or more additional bioconjugates.
1. A composition comprising a glycoconjugate of an E. coli O 25B antigen covalently coupled to a carrier protein, wherein the E. coli O 25B antigen comprises the structure of Formula O25B′:
wherein n is an integer of 1 to 30.
2. The composition of claim 1 , wherein the carrier protein is selected from the group consisting of detoxified Exotoxin A of P. aeruginosa (EPA), CRM197, maltose binding protein (MBP), Diphtheria toxoid, Tetanus toxoid, detoxified hemolysin A of S. aureus , clumping factor A, clumping factor B, E. coli FimH, E. coli FimHC, E. coli heat labile enterotoxin, detoxified variants of E. coli heat labile enterotoxin, Cholera toxin B subunit (CTB), cholera toxin, detoxified variants of cholera toxin, E. coli Sat protein, the passenger domain of E. coli Sat protein, Streptococcus pneumoniae Pneumolysin and detoxified variants thereof, C. jejuni AcrA, and C. jejuni natural glycoproteins.
3. The composition of claim 2 , wherein the carrier protein is detoxified EPA or CRM197.
4. The composition of claim 1 , wherein the E. coli O25B antigen is covalently coupled to an Asn residue in the carrier protein.
5. The composition of claim 4 , wherein the Asn residue of the carrier protein is positioned in the consensus sequence Asp(Glu)-X-Asn-Z-Ser(Thr), wherein X and Z are independently selected from any natural amino acid except Pro (SEQ ID NO:15).
6. The composition of claim 1 , further comprising a glycoconjugate of an E. coli O1 antigen covalently coupled to a carrier protein, a glycoconjugate of an E. coli O2 antigen covalently coupled to a carrier protein, and a glycoconjugate of an E. coli O6 antigen covalently coupled to a carrier protein.
7. The composition of claim 6 , wherein the E. coli O1 antigen comprises the structure of Formula O1A′:
the E. coli O2 antigen comprises the structure of Formula O2′:
and
the O6 antigen comprises the structure of Formula O6GlcNAc′:
wherein n is an integer of 1 to 30.
8. A composition comprising an E. coli O25B antigen and at least one of the following: (i) an E. coli O1 antigen, (ii) an E. coli O2 antigen, and/or (iii) an E. coli O6 antigen; wherein at least the E. coli O25B antigen is covalently coupled to a carrier protein.
9. The composition of claim 8 , wherein the E. coli O25B antigen comprises the structure of Formula O25B′:
wherein n is an integer of 1 to 30.
10. The composition of claim 9 , wherein the carrier protein is selected from the group consisting of detoxified Exotoxin A of P. aeruginosa (EPA), CRM197, maltose binding protein (MBP), Diphtheria toxoid, Tetanus toxoid, detoxified hemolysin A of S. aureus , clumping factor A, clumping factor B, E. coli FimH, E. coli FimHC, E. coli heat labile enterotoxin, detoxified variants of E. coli heat labile enterotoxin, Cholera toxin B subunit (CTB), cholera toxin, detoxified variants of cholera toxin, E. coli Sat protein, the passenger domain of E. coli Sat protein, Streptococcus pneumoniae Pneumolysin and detoxified variants thereof, C. jejuni AcrA, and C. jejuni natural glycoproteins.
11. The composition of claim 10 , wherein the carrier protein is detoxified EPA or CRM197.
12. The composition of claim 11 , wherein the E. coli O 25B antigen is covalently coupled to an Asn residue in the carrier protein.
13. The composition of claim 11 , wherein the Asn residue of the carrier protein is positioned in the consensus sequence Asp(Glu)-X-Asn-Z-Ser(Thr), wherein X and Z are independently selected from any natural amino acid except Pro (SEQ ID NO:15).
14. The composition of claim 8 , wherein the E. coli 01 antigen comprises the structure of Formula O1A′:
the E. coli O 2 antigen comprises the structure of Formula O2′:
and
the O6 antigen comprises the structure of Formula O6GlcNAc′:
wherein n is an integer of 1 to 30.
15. A composition comprising (i) an E. coli O25B macromolecule, (ii) an E. coli O1 macromolecule, (iii) an E. coli O2 macromolecule, and (iv) an E. coli O6 macromolecule, wherein at least the E. coli O25B macromolecule is conjugated to a carrier protein.
16. The composition of claim 15 , wherein the E. coli O25B macromolecule comprises the structure of Formula O25B′:
wherein n is an integer of 1 to 30.
17. The composition of claim 15 , wherein the E. coli O1 macromolecule is an E. coli O1A macromolecule and the E. coli O6 macromolecule comprises a branching Glc monosaccharide.
18. The composition of claim 15 , wherein each of the E. coli macromolecules is a glycoconjugate comprising a carrier protein.
19. The composition of claim 5 , wherein the glycoconjugate of the E. coli O25B antigen is a bioconjugate and the composition further comprises a pharmaceutically acceptable carrier.
20. The composition of claim 19 , where the carrier protein comprises the amino acid sequence of SEQ ID NO: 13.
21. The composition of claim 5 , wherein the glycoconjugate of the E. coli O25B antigen is a bioconjugate and the composition further comprises a) an E. coli O1 bioconjugate comprising the O1A′ antigen covalently bound to an Asn residue of a protein carrier, wherein O1A′ antigen has the structure:
b) an E. coli O2 bioconjugate comprising the O2′ antigen covalently bound to an Asn residue of a protein carrier, wherein the O2′ antigen has the structure:
and
c) an E. coli O6 bioconjugate comprising the O6′ antigen covalently bound to an Asn residue of a protein carrier, wherein the O6′ antigen has the structure:
wherein n is an integer of 1 to 30; wherein the composition further comprises a pharmaceutically acceptable carrier.
22. The composition of claim 21 , where each carrier protein comprises the amino acid sequence of SEQ ID NO: 13.