Identification and Characterization of a Lipopolysaccharide alpha,2,3-Sialyltransferase from the Human Pathogen Helicobacter bizzozeronii
2012 (English)In: Journal of Bacteriology, ISSN 0021-9193, E-ISSN 1098-5530, Vol. 194, no 10, 2540-2550 p.Article in journal (Refereed) Published
Terminal sialic acid in the lipopolysaccharides (LPSs) of mucosal pathogens is an important virulence factor. Here we report the characterization of a Helicobacter sialyltransferase involved in the biosynthesis of sialylated LPS in Helicobacter bizzozeronii, the only non-pylori gastric Helicobacter species isolated from humans thus far. Starting from the genome sequences of canine and human strains, we identified potential sialyltransferases downstream of three genes involved in the biosynthesis of N-acetylneuraminic acid. One of these candidates showed monofunctional alpha,2,3-sialyltransferase activity with a preference for N-acetyllactosamine as a substrate. The LPSs from different strains were shown by SDS-PAGE and high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) to contain sialic acid after neuraminidase treatment. The expression of this sialyltransferase and sialyl-LPS appeared to be a phase-variable characteristic common to both human and canine H. bizzozeronii strains. The sialylation site of the LPSs of two H. bizzozeronii strains was determined to be NeuAc-Hex-HexNAc, suggesting terminal 3-sialyl-LacNAc. Moreover, serological typing revealed the possible presence of sialyl-Lewis X in two additional strains, indicating that H. bizzozeronii could also mimic the surface glycans of mammalian cells. The expression of sialyl-glycans may influence the adaptation process of H. bizzozeronii during the host jump from dogs to humans.
Place, publisher, year, edition, pages
American Society for Microbiology , 2012. Vol. 194, no 10, 2540-2550 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-77868DOI: 10.1128/JB.00126-12ISI: 000303693400014OAI: oai:DiVA.org:liu-77868DiVA: diva2:529695
Funding Agencies|Academy of Finland (FCoE MiFoSa)|118602141140|Academy of Finland|132940|Research Foundation of the University of Helsinki||CIMO India|25.11.2009/FM-09-6586|Canadian Institutes of Health Research|MOP84272|2012-05-312012-05-312012-05-31