Sugar transport in Sulfolobus solfataricus is mediated by two families of binding protein-dependent ABC transporters.
The extreme thermoacidophilic archaeon Sulfolobus solfataricus grows optimally at 80 degrees 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.
Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands.
M G
MG
Elferink
S V
SV
Albers
W N
WN
Konings
A J
AJ
Driessen
D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D019843:Archaeal Proteins; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D002462:Cell Membrane / Q000378:metabolism; D003208:Concanavalin A / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006031:Glycosylation; D008358:Mannose / Q000378:metabolism; D008969:Molecular Sequence Data; D009876:Operon; D017386:Sequence Homology, Amino Acid; D016944:Sulfolobus / Q000235:genetics / Q000378:metabolism*
D018528:ATP-Binding Cassette Transporters; D019843:Archaeal Proteins; C430111:GlcS protein, Sulfolobus solfataricus; D003208:Concanavalin A; D005947:Glucose; D008358:Mannose