Cell wall glycopolymers on the surface of Gram-positive bacteria are fundamental to bacterial physiology and infection biology. Here we identify gacH, a gene in the Streptococcus pyogenes group A carbohydrate (GAC) biosynthetic cluster, in two independent transposon library screens for its ability to confer resistance to zinc and susceptibility to the bactericidal enzyme human group IIA-secreted phospholipase A2. Subsequent structural and phylogenetic analysis of the GacH extracellular domain revealed that GacH represents an alternative class of glycerol phosphate transferase. We detected the presence of glycerol phosphate in the GAC, as well as the serotype c carbohydrate from Streptococcus mutans, which depended on the presence of the respective gacH homologs. Finally, nuclear magnetic resonance analysis of GAC confirmed that glycerol phosphate is attached to approximately 25% of the GAC N-acetylglucosamine side-chains at the C6 hydroxyl group. This previously unrecognized structural modification impacts host-pathogen interaction and has implications for vaccine design.
analysis, gene cluster, cell wall, modification, glycopolymer, rhamnose, streptococcal, Streptococcus pyogenes, phylogenetic
NCBI PubMed ID: 30936502Publication DOI: 10.1038/s41589-019-0251-4Journal NLM ID: 101231976Publisher: New York, NY: Nature Publishing Group
Correspondence: nkorotkova@uky.edu; nsorge3@umcutrecht.nl
Institutions: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden, Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA, Callaghan Innovation, Gracefield, Lower Hutt, New Zealand, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands, Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia, Division of Cardiovascular Medicine and the Gill Heart Institute, University of Kentucky, Lexington, KY, USA, Wound Infections Department, Bacterial Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA, Department of Cell Biology & Molecular Genetics and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA, Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, USA, Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moleculaire et Cellulaire, Valbonne Sophia Antipolis, France
Methods: 13C NMR, 1H NMR, NMR-2D, PCR, GC-MS, X-ray, sugar analysis, 31P NMR, genetic methods, alkaline hydrolysis, crystallography, statistical analysis, LC-MS, phylogenetic analysis
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