Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Pseudomonas aeruginosa [ICD11:
XN5L6 
]
NCBI PubMed ID: 36494359Publication DOI: 10.1038/s41467-022-35131-6Journal NLM ID: 101528555Publisher: London: Nature Publishing Group
Correspondence: P.L. Howell <howell

sickkids.ca>
Institutions: Department of Chemistry, University of Alberta, Edmonton, AB, Canada, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands, Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada, Department of Biochemistry, University of Toronto, Toronto, ON, Canada, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA, Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada, Departement de Microbiologie, Infectiologie et Immunologie, Universite de Montreal, Montreal, QC, Canada, Department of Chemical Biology, Stratingh Institute for Chemistry, University of Groningen, Groningen, The Netherlands, National Research Centre for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang, China
Synthase-dependent secretion systems are a conserved mechanism for producing exopolysaccharides in Gram-negative bacteria. Although widely studied, it is not well understood how these systems are organized to coordinate polymer biosynthesis, modification, and export across both membranes and the peptidoglycan. To investigate how synthase-dependent secretion systems produce polymer at a molecular level, we determined the crystal structure of the AlgK-AlgX (AlgKX) complex involved in Pseudomonas aeruginosa alginate exopolysaccharide acetylation and export. We demonstrate that AlgKX directly binds alginate oligosaccharides and that formation of the complex is vital for polymer production and biofilm attachment. Finally, we propose a structural model for the AlgEKX outer membrane modification and secretion complex. Together, our study provides insight into how alginate biosynthesis proteins coordinate production of a key exopolysaccharide involved in establishing persistent Pseudomonas lung infections.
Pseudomonas aeruginosa, Oligosaccharides, infection, modification, Biofilm, alginate exopolysaccharide, P.aeruginosa AlgK
Structure type: structural motif or average structure
Location inside paper: Fig. 1a
Trivial name: alginate
Compound class: EPS
Methods: PCR, X-ray, ESI-MS, Western blotting, genetic methods, crystallization, enzymatic assay, antibody production, molecular biology methods
3D data: 3D data
NCBI Taxonomy refs (TaxIDs): 287
Show glycosyltransferases
There is only one chemically distinct structure: