Structure and mechanism of biosynthesis of Streptococcus mutans cell wall polysaccharide
Streptococcus mutans, the causative agent of human dental caries, expresses a cell wall attached Serotype c-specific Carbohydrate (SCC) that is critical for cell viability. SCC consists of a polyrhamnose backbone of →3)α-Rha(1 → 2)α-Rha(1→ repeats with glucose (Glc) side-chains and glycerol phosphate (GroP) decorations. This study reveals that SCC has one predominant and two more minor Glc modifications. The predominant Glc modification, α-Glc, attached to position 2 of 3-rhamnose, is installed by SccN and SccM glycosyltransferases and is the site of the GroP addition. The minor Glc modifications are β-Glc linked to position 4 of 3-rhamnose installed by SccP and SccQ glycosyltransferases, and α-Glc attached to position 4 of 2-rhamnose installed by SccN working in tandem with an unknown enzyme. Both the major and the minor β-Glc modifications control bacterial morphology, but only the GroP and major Glc modifications are critical for biofilm formation.
Authors
- Cameron W. Kenner
- Ian Black (ORCID: https://orcid.org/0000-0001-7075-7517)
- Jeffrey S. Rush (ORCID: https://orcid.org/0000-0002-3674-8008)
- Konstantin V. Korotkov (ORCID: https://orcid.org/0000-0002-2182-6843)
- Svetlana Zamakhaeva (ORCID: https://orcid.org/0000-0001-9971-4211)
- Göran Widmalm (ORCID: https://orcid.org/0000-0001-8303-4481)
- Andrew J. Morris (ORCID: https://orcid.org/0000-0003-1910-4865)
- Natalia Korotkova (ORCID: https://orcid.org/0000-0002-8696-4892)
- Parastoo Azadi (ORCID: https://orcid.org/0000-0002-6166-9432)
- Deng Pan (ORCID: https://orcid.org/0000-0002-6475-0463)
- Christian Heiß (ORCID: https://orcid.org/0000-0003-1118-8953)
- Nicholas R. Murner (ORCID: https://orcid.org/0009-0002-7263-7193)
Institutions
- University of Kentucky HealthCare (US)
- University of Kentucky (US)
- Stockholm University (SE)
- University of Georgia (US)
- Soochow University (CN)
- Central Arkansas Veterans Healthcare System (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-01-22
- DOI
- https://doi.org/10.1038/s41467-025-56205-1
- Citations
- 12
- Primary Topic
- Oral microbiology and periodontitis research
- Type
- article
- Field-Weighted Citation Impact
- 16.12
Funders
- National Science Foundation
- U.S. Department of Energy
- Knut och Alice Wallenbergs Stiftelse
- Vetenskapsrådet
- National Institutes of Health
- National Institute of General Medical Sciences
- National Institute of Allergy and Infectious Diseases
- National Institute of Dental and Craniofacial Research
- Division of Electrical, Communications and Cyber Systems
- Basic Energy Sciences
- Chemical Sciences, Geosciences, and Biosciences Division