6YU5

Crystal structure of MhsT in complex with L-valine

6YU5 の概要

• エントリーDOI: 10.2210/pdb6yu5/pdb
• 分子名称: Sodium-dependent transporter, VALINE, SODIUM ION, ... (6 entities in total)
• 機能のキーワード: leut-fold, amino acid transporter, l-valine, transport protein
• 由来する生物種: Bacillus halodurans
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 104197.07

構造登録者

Focht, D.,Neumann, C.,Lyons, J.,Eguskiza Bilbao, A.,Blunck, R.,Malinauskaite, L.,Schwarz, I.O.,Javitch, J.A.,Quick, M.,Nissen, P. (登録日: 2020-04-25, 公開日: 2020-07-15, 最終更新日: 2024-01-24)

主引用文献

Focht, D.,Neumann, C.,Lyons, J.,Eguskiza Bilbao, A.,Blunck, R.,Malinauskaite, L.,Schwarz, I.O.,Javitch, J.A.,Quick, M.,Nissen, P.
A non-helical region in transmembrane helix 6 of hydrophobic amino acid transporter MhsT mediates substrate recognition.
Embo J., 40:e105164-e105164, 2021

PubMed Abstract: MhsT of Bacillus halodurans is a transporter of hydrophobic amino acids and a homologue of the eukaryotic SLC6 family of Na -dependent symporters for amino acids, neurotransmitters, osmolytes, or creatine. The broad range of transported amino acids by MhsT prompted the investigation of the substrate recognition mechanism. Here, we report six new substrate-bound structures of MhsT, which, in conjunction with functional studies, reveal how the flexibility of a Gly-Met-Gly (GMG) motif in the unwound region of transmembrane segment 6 (TM6) is central for the recognition of substrates of different size by tailoring the binding site shape and volume. MhsT mutants, harboring substitutions within the unwound GMG loop and substrate binding pocket that mimick the binding sites of eukaryotic SLC6A18/B0AT3 and SLC6A19/B0AT1 transporters of neutral amino acids, exhibited impaired transport of aromatic amino acids that require a large binding site volume. Conservation of a general (G/A/C)ΦG motif among eukaryotic members of SLC6 family suggests a role for this loop in a common mechanism for substrate recognition and translocation by SLC6 transporters of broad substrate specificity.

PubMed: 33155685
DOI: 10.15252/embj.2020105164

実験手法

X-RAY DIFFRACTION (2.6 Å)