Polar flagellin glycan metaheterogeneity of Aeromonas hydrophila strain ATCC 7966T

Fulton, K. M.; Mendoza-Barbera, E.; Tomas, J. M.; Twine, S. M.; Smith, J. C.; Merino, S.

doi:10.1101/2024.05.20.594992

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bioRxiv · 10.1101/2024.05.20.594992

Polar flagellin glycan metaheterogeneity of Aeromonas hydrophila strain ATCC 7966T

Fulton, K. M.·Mendoza-Barbera, E.·Tomas, J. M.·Twine, S. M.·Smith, J. C.·Merino, S.

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Abstract

Motile pathogens often rely upon flagellar motility as an essential virulence factor and in many species the structural flagellin protein is glycosylated. This post-translational modification has been shown to be necessary for proper folding of the flagellin structural proteins and proper function of the flagellar filament in a number of bacterial species. Aeromonas hydrophila is a ubiquitous aquatic pathogen with a constitutively expressed polar flagellum. Using a suite of mass spectrometry techniques, the flagellin FlaA and FlaB structural proteins of A. hydrophila strain ATCC 7966T were shown to be glycosylated with significant metaheterogeneity: heterologous glycans were observed with variable site occupancy. The penta- and hexa-saccharide glycan chains contained a previously unreported pseudaminic acid derivative with a mass of 422 Da as the linking sugar, followed in sequence by two hexoses, an N-acetylglucosamine derivative, a deoxy N-acetylglucosamine derivative, and sometimes an additional N-acetylglucosamine.

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Fulton, K. M., Mendoza-Barbera, E., Tomas, J. M., Twine, S. M., Smith, J. C., Merino, S.. 2024-05-20. Polar flagellin glycan metaheterogeneity of Aeromonas hydrophila strain ATCC 7966T. https://doi.org/10.1101/2024.05.20.594992

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