9I3K
Asymmetric cryo-EM reconstruction of the full-length E. coli transmembrane formate transporter FocA
Summary for 9I3K
| Entry DOI | 10.2210/pdb9i3k/pdb |
| Related | 9G49 9G4D |
| EMDB information | 51034 51035 52595 |
| Descriptor | Formate channel FocA (1 entity in total) |
| Functional Keywords | fnt-transporter, foca, formate, membrane protein |
| Biological source | Escherichia coli K-12 |
| Total number of polymer chains | 5 |
| Total formula weight | 155063.02 |
| Authors | Tueting, C.,Janson, K.,Kyrilis, F.L.,Hamdi, F.,Kastritis, P.L. (deposition date: 2025-01-23, release date: 2025-10-22, Last modification date: 2025-11-05) |
| Primary citation | Tuting, C.,Janson, K.,Kammel, M.,Ihling, C.,Lorenz, J.,Kyrilis, F.L.,Hamdi, F.,Erdmann, C.,Sinz, A.,Sawers, R.G.,Kastritis, P.L. Conserved hydrophilic checkpoints tune FocA-mediated formate:H + symport. Nat Commun, 16:9476-9476, 2025 Cited by PubMed Abstract: FocA belongs to the widespread, evolutionarily ancient formate-nitrite transporter (FNT) family of pentameric anion channels and translocates formic acid bidirectionally. Here, we identify compartmentalized polarity distribution across the complete FocA pore structure - resolved at 2.56 Å - mirrored against a two-fold axis with H209 at its center. A FocA-H209N variant that exhibits an efflux-only channel-like function in vivo reveals a density consistent with formate located directly at N209, abolishing the channel's amphiphilicity. Pyruvate formate-lyase, which generates formate, orients at the cytoplasmic face where formate delivery is regulated by conformational changes in the FocA vestibule. Comparisons with other FNTs suggest a tuning mechanism of formate-specific transport via checkpoints enriched in hydrophilic residues. PubMed: 41145500DOI: 10.1038/s41467-025-65159-3 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (2.87 Å) |
Structure validation
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