{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T06:18:25Z","timestamp":1787811505083,"version":"build-2784847793"},"reference-count":46,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>\n                    <jats:italic>Clostridioides difficile<\/jats:italic>\n                    polysaccharides (PSs) represent useful tools for the study of\n                    <jats:italic>C. difficile<\/jats:italic>\n                    pathogenesis. Water-soluble PS-I (pentaglycosyl-phosphate repeats) and PS-II (hexaglycosyl-phosphate repeats) and phenol-soluble lipoteichoic acid (LTA) PS-III have been previously identified. Most of the LTA PS-III repeats consist of two\n                    <jats:italic>N<\/jats:italic>\n                    -acetyl-glucopyranosamine (GlcNAc) units and glyceric acid (GroA), bridged by an exocyclic phosphodiester: \u2192P-6)-\u03b1-D-GlcNAc-(1-3)-\u03b1-D-GlcNAc-[1-2-GroA]-(6\u2192. Here, we describe a water-soluble PS from an equine\n                    <jats:italic>C. difficile<\/jats:italic>\n                    strain similar to PS-III, but with 6-substituted glucopyranosamine (GlcN) predominantly in the repeat: \u2192P-6)-\u03b1-D-GlcN-(1-3)-\u03b1-D-GlcNAc-[1-2-GroA]-(6\u2192 (coined wsPS-III). For analytical comparisons, the two saccharides, \u03b1-D-GlcN-(1-3)-\u03b1-D-GlcNAc-(1-2)-GroA and \u03b1-D-GlcNAc-(1-3)-\u03b1-D-GlcNAc-(1-2)-GroA, were chemically synthesized, and the transformation product, Gro-(1-P-6)-\u03b1-D-GlcNAc-(1-2)-GroA, was generated by Smith degradation. Pre-existing circulating IgG antibodies in horse sera due to natural exposure reacted with wsPS-III, and inoculation of rabbits with wsPS-III afforded IgG antibodies that reacted with\n                    <jats:italic>C. difficile<\/jats:italic>\n                    . It is postulated that the zwitterionic nature of wsPS-III is the driving force behind the observed solubility and immunogenicity. The glycans presented here will be useful in investigations concerning\n                    <jats:italic>C. difficile<\/jats:italic>\n                    biosynthetic pathways, virulence, antibiotics and vaccines.\n                  <\/jats:p>","DOI":"10.3389\/fimmu.2026.1901286","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T05:34:58Z","timestamp":1787808898000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Clostridioides difficile water-soluble zwitterionic lipoteichoic acid wsPS-III: structure, synthesis, and immunogenicity"],"prefix":"10.3389","volume":"17","author":[{"given":"Zuchao","family":"Ma","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Guelph","place":["Guelph, ON, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brittany","family":"Pequegnat","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Guelph","place":["Guelph, ON, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Douglas","family":"Hodgins","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, University of Guelph","place":["Guelph, ON, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Sagermann","sequence":"additional","affiliation":[{"name":"Stellar Biotechnologies Inc.","place":["Port Hueneme, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeyabarathy","family":"Ganeshapillai","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Guelph","place":["Guelph, ON, Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sharif","family":"Arar","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Guelph","place":["Guelph, ON, 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