Members of the Bacteroidales order are among the most abundant gram-negative bacteria of the human colonic microbiota. These species decorate their cell-surface glycoproteins with fucosylated glycans, which are believed to play important roles in host intestinal colonization. Currently, there is no method for the enrichment of these glycoproteins for their identification. Here, we describe a chemical approach directed toward labeling and detecting fucosylated glycoproteins from cultured Bacteroidales species, namely Bacteroides fragilis and Parabacteroides distasonis. We treated these bacteria with an alkyne-bearing fucose analog, which is metabolically integrated into the bacterial surface fucosylated glycoproteins. The alkyne-tagged glycoproteins can then react with azide-bearing biophysical probes via bioorthogonal click chemistry for detection or glycoproteomic analysis.
Bibliographical noteFunding Information:
This work was supported by the National Institutes of Health (GM080585 to P.W.) and startup funds from Albert Einstein College of Medicine (to P.W.). C.B. is supported by the NIH training grant T32 GM007491. We thank Professor Laura Comstock for providing B. fragilis Δ fkp and Δ gmd mutants, and Professor Michael Malamy for providing B. fragilis 638R and pADB242A.
- Click chemistry
- Fucosylated glycans
- Metabolic engineering