4RP8

Bacterial vitamin C transporter UlaA/SgaT in P21 form

Summary for 4RP8

• Entry DOI: 10.2210/pdb4rp8/pdb
• Related: 4RP9
• Descriptor: Ascorbate-specific permease IIC component UlaA, ASCORBIC ACID, nonyl beta-D-glucopyranoside, ... (4 entities in total)
• Functional Keywords: pts, vitamin c transporter, l-ascorbate, l-ascorbate-6-p, membrane protein
• Biological source: Escherichia coli K-12
• Cellular location: Cell inner membrane ; Multi-pass membrane protein : P39301
• Total number of polymer chains: 2
• Total formula weight: 102190.96

Authors

Wang, J.W. (deposition date: 2014-10-29, release date: 2015-03-04, Last modification date: 2023-11-08)

Primary citation

Luo, P.,Yu, X.,Wang, W.,Fan, S.,Li, X.,Wang, J.
Crystal structure of a phosphorylation-coupled vitamin C transporter.
Nat.Struct.Mol.Biol., 22:238-241, 2015

PubMed Abstract: Bacteria use vitamin C (L-ascorbic acid) as a carbon source under anaerobic conditions. The phosphoenolpyruvate-dependent phosphotransferase system (PTS), comprising a transporter (UlaA), a IIB-like enzyme (UlaB) and a IIA-like enzyme (UlaC), is required for the anaerobic uptake of vitamin C and its phosphorylation to L-ascorbate 6-phosphate. Here, we present the crystal structures of vitamin C-bound UlaA from Escherichia coli in two conformations at 1.65-Å and 2.35-Å resolution. UlaA forms a homodimer and exhibits a new fold. Each UlaA protomer consists of 11 transmembrane segments arranged into a 'V-motif' domain and a 'core' domain. The V motifs form the interface between the two protomers, and the core-domain residues coordinate vitamin C. The alternating access of the substrate from the opposite side of the cell membrane may be achieved through rigid-body rotation of the core relative to the V motif.

PubMed: 25686089
DOI: 10.1038/nsmb.2975

Experimental method

X-RAY DIFFRACTION (2.359 Å)