NZ 597923 Disclosed is a microbial cell transformed with a vector comprising a nucleotide sequence selected from the group consisting of a nucleic acid molecule consisting of a nucleic acid sequence as represented in Figure 1 a, as defined in the specification a nucleic acid molecule consisting of a nucleic acid sequence that hybridises under stringent hybridisation conditions to the nucleic acid molecule in (i) and which encodes an polypeptide wherein said cell expresses a recombinant polypeptide which is a substrate for said oligosaccharyltransferase polypeptide. Also disclosed is a vaccine composition comprising a bacterial glycoconjugate antigenic polypeptide, or part thereof, said polypeptide including at least one peptide motif consisting of the amino acid sequence: Asp/Glu-Xaa1-Asn-Xaa2-Ser/Thr, wherein Xaa1 and Xaa2 is any amino acid except proline and further wherein said motif is modified by a oligosaccharyltransferase polypeptide selected from the group consisting of: a nucleic acid molecule consisting of a nucleic acid sequence as represented in Figure 1 a, as defined in the specification a nucleic acid molecule consisting of a nucleic acid sequence that hybridises under stringent hybridisation conditions to the nucleic acid molecule in (i) and which encodes an oligosaccharyltransferase polypeptide.
