6B2B

Crystal structure of fluoride channel Fluc Ec2 F83M Mutant

6B2B の概要

• エントリーDOI: 10.2210/pdb6b2b/pdb
• 分子名称: Fluoride ion transporter CrcB, monobody, DECYL-BETA-D-MALTOPYRANOSIDE, ... (6 entities in total)
• 機能のキーワード: alpha helix, ion channel, membrane protein, transport protein
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 49363.28

構造登録者

Last, N.B.,Sun, S.,Pham, M.C.,Miller, C. (登録日: 2017-09-19, 公開日: 2017-10-11, 最終更新日: 2023-10-04)

主引用文献

Last, N.B.,Sun, S.,Pham, M.C.,Miller, C.
Molecular determinants of permeation in a fluoride-specific ion channel.
Elife, 6:-, 2017

PubMed Abstract: Fluoride ion channels of the Fluc family combat toxicity arising from accumulation of environmental F. Although crystal structures are known, the densely packed pore region has precluded delineation of the ion pathway. Here we chart out the Fluc pore and characterize its chemical requirements for transport. A ladder of H-bond donating residues creates a 'polar track' demarking the ion-conduction pathway. Surprisingly, while track polarity is well conserved, polarity is nonetheless functionally dispensable at several positions. A threonine at one end of the pore engages in vital interactions through its β-branched methyl group. Two critical central phenylalanines that directly coordinate F through a quadrupolar-ion interaction cannot be functionally substituted by aromatic, non-polar, or polar sidechains. The only functional replacement is methionine, which coordinates F through its partially positive γ-methylene in mimicry of phenylalanine's quadrupolar interaction. These results demonstrate the unusual chemical requirements for selectively transporting the strongly H-bonding F anion.

PubMed: 28952925
DOI: 10.7554/eLife.31259

実験手法

X-RAY DIFFRACTION (2.6 Å)