EC Number   |
General Information |
Reference |
|---|
  7.5.2.3 | evolution |
the ABC uptake system associated with SO-BP is conserved in a number of bacterial species in firmicutes, actinobacteria, and proteobacteria. Consensus phylogenetic tree of SO-BP homologues, the phylogenetic tree is constructed using the neighbor-joining method, overview |
751123 |
| 7.5.2.3 | more |
the complex structures with substrates Sop3-5s bound can be overlaid well, molecular dynamics and three-dimensional structure modeling, architecture of the ligand-binding site, overview. Hydrogen bonds play a pivotal role in stabilizing the SO-BP-Sopn complexes. Thr95, Thr96, Glu147, and Gly301 form hydrogen bonds with the hydroxyl groups of unit A. Glu45 and Tyr145 form hydrogen bonds with the hydroxyl groups of unit B. Asp193 and Gln197 form hydrogen bonds with the hydroxyl groups at unit C. These interactions are shared among the Sopn-bound structures. Contribution of interactions at unit C to complex stability |
751123 |
| 7.5.2.3 | physiological function |
ATP-binding cassette (ABC)2-type transporters are widely distributed in living organisms, forming one of the largest protein superfamilies. ABC transporters utilize the free energy obtained from ATP hydrolysis to import or export a wide variety of molecules across cellular membranes. They share a common architecture consisting of two transmembrane domains (TMDs) and intracellular nucleotide-binding domains (NBDs). In bacterial ABC importers, an additional domain, a solute (or substrate)-binding protein (SBP), serves as an initial receptor that specifically binds to ligands with high affinity, delivers them to TMDs, and stimulates the ATPase activity. Genes Lin1841 and Lin1842-1843 from the Gram-positive bacterium Listeria innocua encode an SBP and TMDs, respectively. The transporter is responsible for uptake of beta-1,2-Glucan and its shorter oligosaccharides (sophorooligosaccharides, Sopns). beta-1,2-Glucans are bacterial carbohydrates that exist in cyclic or linear forms and play an important role in infections and symbioses involving Gram-negative bacteria. Sopns are captured and imported into the bacterial cell by Sopn-binding protein (SO-BP, Lin1841) associated with the ATP-binding cassette (ABC) transporter. A key factor determining the specificity for chain length of ligands is the polar interactions toward unit C |
751123 |
