4RFS
Structure of a pantothenate energy coupling factor transporter
Summary for 4RFS
| Entry DOI | 10.2210/pdb4rfs/pdb |
| Descriptor | Energy-coupling factor transporter ATP-binding protein EcfA2, Energy-coupling factor transporter ATP-binding protein EcfA1, Substrate binding pritein S, ... (4 entities in total) |
| Functional Keywords | transporter, ecf, hydrolase, transport protein |
| Biological source | Lactobacillus brevis More |
| Cellular location | Cell membrane ; Peripheral membrane protein : Q03PY6 Q03PY5 Cell membrane ; Multi-pass membrane protein : Q03PY7 |
| Total number of polymer chains | 4 |
| Total formula weight | 116876.34 |
| Authors | |
| Primary citation | Zhang, M.,Bao, Z.,Zhao, Q.,Guo, H.,Xu, K.,Wang, C.,Zhang, P. Structure of a pantothenate transporter and implications for ECF module sharing and energy coupling of group II ECF transporters. Proc.Natl.Acad.Sci.USA, 111:18560-18565, 2014 Cited by PubMed Abstract: Energy-coupling factor (ECF) transporters are a unique group of ATP-binding cassette (ABC) transporters responsible for micronutrient uptake from the environment. Each ECF transporter is composed of an S component (or EcfS protein) and T/A/A' components (or EcfT/A/A' proteins; ECF module). Among the group II ECF transporters, several EcfS proteins share one ECF module; however, the underlying mechanism remains unknown. Here we report the structure of a group II ECF transporter-pantothenate transporter from Lactobacillus brevis (LbECF-PanT), which shares the ECF module with the folate and hydroxymethylpyrimidine transporters (LbECF-FolT and LbECF-HmpT). Structural and mutational analyses revealed the residues constituting the pantothenate-binding pocket. We found that although the three EcfS proteins PanT, FolT, and HmpT are dissimilar in sequence, they share a common surface area composed of the transmembrane helices 1/2/6 (SM1/2/6) to interact with the coupling helices 2/3 (CH2/3) of the same EcfT. CH2 interacts mainly with SM1 via hydrophobic interactions, which may modulate the sliding movement of EcfS. CH3 binds to a hydrophobic surface groove formed by SM1, SM2, and SM6, which may transmit the conformational changes from EcfA/A' to EcfS. We also found that the residues at the intermolecular surfaces in LbECF-PanT are essential for transporter activity, and that these residues may mediate intermolecular conformational transmission and/or affect transporter complex stability. In addition, we found that the structure of EcfT is conformationally dynamic, which supports its function as a scaffold to mediate the interaction of the ECF module with various EcfS proteins to form different transporter complexes. PubMed: 25512487DOI: 10.1073/pnas.1412246112 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (3.232 Å) |
Structure validation
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