Halide-selective, proton-coupled anion transport by phenylthiosemicarbazones.
Anion transport
Hydrogen bonding
Switchable receptors
Thiosemicarbazones
Journal
Biochimica et biophysica acta. Biomembranes
ISSN: 1879-2642
Titre abrégé: Biochim Biophys Acta Biomembr
Pays: Netherlands
ID NLM: 101731713
Informations de publication
Date de publication:
01 02 2022
01 02 2022
Historique:
received:
23
08
2021
revised:
14
11
2021
accepted:
22
11
2021
pubmed:
4
12
2021
medline:
19
2
2022
entrez:
3
12
2021
Statut:
ppublish
Résumé
Phenylthiosemicarbazones (PTSCs) are proton-coupled anion transporters with pH-switchable behaviour known to be regulated by an imine protonation equilibrium. Previously, chloride/nitrate exchange by PTSCs was found to be inactive at pH 7.2 due to locking of the thiourea anion binding site by an intramolecular hydrogen bond, and switched ON upon imine protonation at pH 4.5. The rate-determining process of the pH switch, however, was not examined. We here develop a new series of PTSCs and demonstrate their conformational behaviour by X-ray crystallographic analysis and pH-switchable anion transport properties by liposomal assays. We report the surprising finding that the protonated PTSCs are extremely selective for halides over oxyanions in membrane transport. Owing to the high chloride over nitrate selectivity, the pH-dependent chloride/nitrate exchange of PTSCs originates from the rate-limiting nitrate transport process being inhibited at neutral pH.
Identifiants
pubmed: 34861222
pii: S0005-2736(21)00276-5
doi: 10.1016/j.bbamem.2021.183828
pii:
doi:
Substances chimiques
Anions
0
Chlorides
0
Nitrates
0
Protons
0
Thiosemicarbazones
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
183828Informations de copyright
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