Maltodextrin transport in the extremely thermophilic, lignocellulose degrading bacterium <i>Anaerocellum bescii</i> (f. <i>Caldicellulosiruptor bescii</i> )

Here, we reveal the biophysical and structural basis for oligosaccharide transport by two maltodextrin ATP-binding cassette (ABC) transporters in <i>Anaerocellum bescii</i>. This is the first biophysical characterization of carbohydrate uptake in this organism and establishes a workflow for characterizing other oligosaccharide transporters in <i>A. bescii</i> and similar biomass-degrading thermophiles of interest for lignocellulosic bioprocessing. By deciphering the mechanisms underlying high-affinity sugar uptake in <i>A. bescii</i>, we shed light on an underexplored step between extracellular lignocellulose degradation and intracellular conversion of sugars to metabolic products. This understanding will expand opportunities for harnessing sugar transport in thermophiles to reshape lignocellulose bioprocessing as part of a renewable bioeconomy.