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A general protein O-glycosylation machinery conserved in Burkholderia species improves bacterial fitness and elicits glycan immunogenicity in humans.

ABSTRACT: The Burkholderia genus encompasses many Gram-negative bacteria living in the rhizosphere. Some Burkholderia species can cause life-threatening human infections, highlighting the need for clinical interventions targeting specific lipopolysaccharide proteins. Burkholderia cenocepacia O-linked protein glycosylation has been reported, but the chemical structure of the O-glycan and the machinery required for its biosynthesis are unknown and could reveal potential therapeutic targets. Here, using bioinformatics approaches, gene-knockout mutants, purified recombinant proteins, LC-MS-based analyses of O-glycans, and NMR-based structural analyses, we identified a B. cenocepacia O-glycosylation (ogc) gene cluster necessary for synthesis, assembly, and membrane translocation of a lipid-linked O-glycan, as well as its structure, which consists of a ?-Gal-(1,3)-?-GalNAc-(1,3)-?-GalNAc trisaccharide. We demonstrate that the ogc cluster is conserved in the Burkholderia genus, and we confirm the production of glycoproteins with similar glycans in the Burkholderia species: B. thailandensis, B. gladioli, and B. pseudomallei Furthermore, we show that absence of protein O-glycosylation severely affects bacterial fitness and accelerates bacterial clearance in a Galleria mellonella larva infection model. Finally, our experiments revealed that patients infected with B. cenocepacia, Burkholderia multivorans, B. pseudomallei, or Burkholderia mallei develop O-glycan-specific antibodies. Together, these results highlight the importance of general protein O-glycosylation in the biology of the Burkholderia genus and its potential as a target for inhibition or immunotherapy approaches to control Burkholderia infections.

SUBMITTER: Fathy Mohamed Y

PROVIDER: S-EPMC6737235 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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A general protein O-glycosylation machinery conserved in Burkholderia species improves bacterial fitness and elicits glycan immunogenicity in humans.

Fathy Mohamed Yasmine Y Scott Nichollas E NE Molinaro Antonio A Creuzenet Carole C Ortega Ximena X Lertmemongkolchai Ganjana G Tunney Michael M MM Green Heather H Jones Andrew M AM DeShazer David D Currie Bart J BJ Foster Leonard J LJ Ingram Rebecca R De Castro Cristina C Valvano Miguel A MA

The Journal of biological chemistry 20190726 36

The Burkholderia genus encompasses many Gram-negative bacteria living in the rhizosphere. Some Burkholderia species can cause life-threatening human infections, highlighting the need for clinical interventions targeting specific lipopolysaccharide proteins. Burkholderia cenocepacia O-linked protein glycosylation has been reported, but the chemical structure of the O-glycan and the machinery required for its biosynthesis are unknown and could reveal potential therapeut ...[more]

PMID: 31350337

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Dataset Information

A general protein O-glycosylation machinery conserved in Burkholderia species improves bacterial fitness and elicits glycan immunogenicity in humans.

Publications

A general protein <i>O-</i>glycosylation machinery conserved in <i>Burkholderia</i> species improves bacterial fitness and elicits glycan immunogenicity in humans.

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