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Updated: Jun 3, 2026

Lipid Exchange Assay in Living Cells
Published on: March 21, 2025
Using small molecules to facilitate exchange of bicarbonate and chloride anions across liposomal membranes
Jeffery T Davis1, Philip A Gale, Oluyomi A Okunola
1Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA. jdavis@umd.edu
Abstract:
Bicarbonate is involved in a wide range of biological processes, which include respiration, regulation of intracellular pH and fertilization. In this study we use a combination of NMR spectroscopy and ion-selective electrode techniques to show that the natural product prodigiosin, a tripyrrolic molecule produced by microorganisms such as Streptomyces and Serratia, facilitates chloride/bicarbonate exchange (antiport) across liposomal membranes. Higher concentrations of simple synthetic molecules based on a 4,6-dihydroxyisophthalamide core are also shown to facilitate this antiport process. Although it is well known that proteins regulate Cl(-)/HCO(3)(-) exchange in cells, these results suggest that small molecules may also be able to regulate the concentration of these anions in biological systems.
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