Sugar transport in Sulfolobus solfataricus is mediated by two families of binding protein‐dependent ABC transporters

• Published in: Molecular microbiology Vol. 39; no. 6; pp. 1494 - 1503
• Main Authors: Elferink, Marieke G. L., Albers, Sonja‐V., Konings, Wil N., Driessen, Arnold J. M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science, Ltd 01.03.2001; Blackwell Publishing Ltd
• Subjects: Acidophilic archaea; Amino Acid Sequence; Archaeal Proteins; ATP-Binding Cassette Transporters - genetics; ATP-Binding Cassette Transporters - metabolism; Biological Transport; Carbohydrate Metabolism; Cell Membrane - metabolism; Concanavalin A - metabolism; Glucose - metabolism; Glycosylation; Mannose - metabolism; Molecular Sequence Data; Operon; Sequence Homology, Amino Acid; sugar transport; Sulfolobus - genetics; Sulfolobus - metabolism; Sulfolobus solfataricus
• ISSN: 0950-382X; 1365-2958
• DOI: 10.1046/j.1365-2958.2001.02336.x

The extreme thermoacidophilic archaeon Sulfolobus solfataricus grows optimally at 80°C and pH 3 and uses a variety of sugars as sole carbon and energy source. Glucose transport in this organism is mediated by a high‐affinity binding protein‐dependent ATP‐binding cassette (ABC) transporter. Sugar‐binding studies revealed the presence of four additional membrane‐bound binding proteins for arabinose, cellobiose, maltose and trehalose. These glycosylated binding proteins are subunits of ABC transporters that fall into two distinct groups: (i) monosaccharide transporters that are homologous to the sugar transport family containing a single ATPase and a periplasmic‐binding protein that is processed at an unusual site at its amino‐terminus; (ii) di‐ and oligosaccharide transporters, which are homologous to the family of oligo/dipeptide transporters that contain two different ATPases, and a binding protein that is synthesized with a typical bacterial signal sequence. The latter family has not been implicated in sugar transport before. These data indicate that binding protein‐dependent transport is the predominant mechanism of transport for sugars in S. solfataricus.