“Just a spoonful of sugar...”: import of sialic acid across bacterial cell membranes
Eukaryotic cell surfaces are decorated with a complex array of glycoconjugates that are usually capped with sialic acids, a large family of over 50 structurally distinct nine-carbon amino sugars, the most common member of which is N-acetylneuraminic acid. Once made available through the action of neuraminidases, bacterial pathogens and commensals utilise host-derived sialic acid by degrading it for energy or repurposing the sialic acid onto their own cell surface to camouflage the bacterium from the immune system. A functional sialic acid transporter has been shown to be essential for the uptake of sialic acid in a range of human bacterial pathogens and important for host colonisation and persistence. Here, we review the state-of-play in the field with respect to the molecular mechanisms by which these bio-nanomachines transport sialic acids across bacterial cell membranes.
KeywordsSialic acid ABC transporter TRAP transporter Sodium solute symporters NanT Porins
R.C.J.D. and R.A.N. acknowledge the following for funding support, in part: (1) the New Zealand Royal Society Marsden Fund (15-UOC032) and (2) the Biomolecular Interaction Centre, University of Canterbury. The project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 608743 (to R.F.). This work was also supported by grants from the Swedish Research Council (2011-5790 to R.F.), the Swedish Research Council Formas (2010-1759 to R.F. and 221-2013-730 to W.Y.W.), the Swedish Governmental Agency for Innovation Systems (VINNOVA) (2013-04655 and 2017-00180 to R.F.), Carl Tryggers Stiftelse för Vetenskaplig Forskning (11:147 to R.F.), EMBO (1163-2014 to P.G. and 584-2014 to R.A.N.) and the Centre for Antibiotic Resistance Research (CARe) at the University of Gothenburg (to R.F.).
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Conflict of interest
Rachel A. North declares that she has no conflict of interest. Christopher R. Horne declares that he has no conflict of interest. James S. Davies declares that he has no conflict of interest. Daniela M. Remus declares that she has no conflict of interest. Andrew C. Muscroft-Taylor declares that he has no conflict of interest. Parveen Goyal declares that he has no conflict of interest. Weixiao Yuan Wahlgren declares that she has no conflict of interest. S. Ramaswamy declares that he has no conflict of interest. Rosmarie Friemann declares that she has no conflict of interest. Renwick C. J. Dobson declares that he has no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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