Tripartite ATP-Independent Periplasmic (Trap) Transporters Use an Arginine-Mediated Selectivity Filter for High Affinity Substrate Binding.
Fischer, M., Hopkins, A.P., Severi, E., Hawkhead, J., Bawdon, D., Watts, A.G., Hubbard, R.E., Thomas, G.H.(2015) J Biol Chem 290: 27113
- PubMed: 26342690 
- DOI: 10.1074/jbc.M115.656603
- Primary Citation of Related Structures:  
2XWI, 2XWK, 2XWO, 2XWV - PubMed Abstract: 
Tripartite ATP-independent periplasmic (TRAP) transporters are secondary transporters that have evolved an obligate dependence on a substrate-binding protein (SBP) to confer unidirectional transport. Different members of the DctP family of TRAP SBPs have binding sites that recognize a diverse range of organic acid ligands but appear to only share a common electrostatic interaction between a conserved arginine and a carboxylate group in the ligand ...