Post-translational modification by the Pgf glycosylation machinery modulates Streptococcus mutans OMZ175 physiology and virulence.

Autor: de Mojana di Cologna N; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Andresen S; Department of Microbiology, University of Georgia, Athens, Georgia, USA.; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA., Samaddar S; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Archer-Hartmann S; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA., Rogers AM; Department of Microbiology, University of Georgia, Athens, Georgia, USA.; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA., Kajfasz JK; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Ganguly T; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Garcia BA; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Saengpet I; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Peterson AM; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Azadi P; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA., Szymanski CM; Department of Microbiology, University of Georgia, Athens, Georgia, USA.; Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA., Lemos JA; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA., Abranches J; Department of Oral Biology, University of Florida, College of Dentistry, Gainesville, Florida, USA.
Jazyk: angličtina
Zdroj: Molecular microbiology [Mol Microbiol] 2024 Aug; Vol. 122 (2), pp. 133-151. Date of Electronic Publication: 2023 Nov 16.
DOI: 10.1111/mmi.15190
Abstrakt: Streptococcus mutans is commonly associated with dental caries and the ability to form biofilms is essential for its pathogenicity. We recently identified the Pgf glycosylation machinery of S. mutans, responsible for the post-translational modification of the surface-associated adhesins Cnm and WapA. Since the four-gene pgf operon (pgfS-pgfM1-pgfE-pgfM2) is part of the S. mutans core genome, we hypothesized that the scope of the Pgf system goes beyond Cnm and WapA glycosylation. In silico analyses and tunicamycin sensitivity assays suggested a functional overlap between the Pgf machinery and the rhamnose-glucose polysaccharide synthesis pathway. Phenotypic characterization of pgf mutants (ΔpgfS, ΔpgfE, ΔpgfM1, ΔpgfM2, and Δpgf) revealed that the Pgf system is important for biofilm formation, surface charge, membrane stability, and survival in human saliva. Moreover, deletion of the entire pgf operon (Δpgf strain) resulted in significantly impaired colonization in a rat oral colonization model. Using Cnm as a model, we showed that Cnm is heavily modified with N-acetyl hexosamines but it becomes heavily phosphorylated with the inactivation of the PgfS glycosyltransferase, suggesting a crosstalk between these two post-translational modification mechanisms. Our results revealed that the Pgf machinery contributes to multiple aspects of S. mutans pathobiology that may go beyond Cnm and WapA glycosylation.
(© 2023 John Wiley & Sons Ltd.)
Databáze: MEDLINE
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