Unraveling the kinetics and pharmacology of human PepT1 using solid supported membrane-based electrophysiology

Bioelectrochemistry. 2023 Sep 16;155:108573. doi: 10.1016/j.bioelechem.2023.108573. Online ahead of print.ABSTRACTThe human Peptide Transporter 1 (hPepT1) is known for its broad substrate specificity and its ability to transport (pro-)drugs. Here, we present an in-depth comprehensive study of hPepT1 and its interactions with various substrates via solid supported membrane-based electrophysiology (SSME). Using hPepT1-containing vesicles, we could not identify any peptide induced pre-steady-state currents, indicating that the recorded peak currents reflect steady-state transport. Electrogenic co-transport of H+/glycylglycine (GlyGly) was observed across a pH range of 5.0 to 9.0. The pH dependence is described by a bell-shaped activity curve and two pK values. KM and relative Vmax values of various canonical and non-canonical peptide substrates were contextualized with current mechanistic understandings of hPepT1. Finally, specific inhibition was observed for various inhibitors in a high throughput format, and IC50 values are reported. Taken together, these findings contribute to promoting the design and analysis of pharmacologically relevant substances.PMID:37748262 | DOI:10.1016/j.bioelechem.2023.108573
Source: Bioelectrochemistry - Category: Biochemistry Authors: Source Type: research