1 VaxNewMo LLC, St. Louis, MO, 63108, USA. christian.harding@vaxnewmo.com.
2 Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2R3, Canada.
3 Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montreal, QC, H4B 1R6, Canada.
4 Department of Microbiology and Immunology, Institute for Infection and Immunity, University of Melbourne at the Peter Doherty, Parkville, VIC, 3010, Australia.
5 Swine and Poultry Infectious Diseases Research Center, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte Street, St-Hyacinthe, QC, J2S 2M2, Canada.
6 Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, 63110, USA.
7 Department of Microbiology and Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA.
8 VaxNewMo LLC, St. Louis, MO, 63108, USA. mariofeldman@wustl.edu.
9 Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, 63110, USA. mariofeldman@wustl.edu.

A platform for glycoengineering a polyvalent pneumococcal bioconjugate vaccine using E. coli as a host.

Nat Commun. 2019 02 21;10(1):891

Authors: Harding CM, Nasr MA, Scott NE, Goyette-Desjardins G, Nothaft H, Mayer AE, Chavez SM, Huynh JP, Kinsella RL, Szymanski CM, Stallings CL, Segura M, Feldman MF

Abstract

Chemical synthesis of conjugate vaccines, consisting of a polysaccharide linked to a protein, can be technically challenging, and in vivo bacterial conjugations (bioconjugations) have emerged as manufacturing alternatives. Bioconjugation relies upon an oligosaccharyltransferase to attach polysaccharides to proteins, but currently employed enzymes are not suitable for the generation of conjugate vaccines when the polysaccharides contain glucose at the reducing end, which is the case for ~75% of Streptococcus pneumoniae capsules. Here, we use an O-linking oligosaccharyltransferase to generate a polyvalent pneumococcal bioconjugate vaccine with polysaccharides containing glucose at their reducing end. In addition, we show that different vaccine carrier proteins can be glycosylated using this system. Pneumococcal bioconjugates are immunogenic, protective and rapidly produced within E. coli using recombinant techniques. These proof-of-principle experiments establish a platform to overcome limitations of other conjugating enzymes enabling the development of bioconjugate vaccines for many important human and animal pathogens.

PMID: 30792408 [PubMed - indexed for MEDLINE]