The human intestinal H~+/oligopeptide cotransporter hPEPT1 transports differently-charged dipeptides with identical electrogenic properties

摘要

The human intestinal H+/oligopeptide cotransporter hPEPT1, expressed in Xenopus oocytes, transported neutral, anionic and cationic dipeptides with identical electrogenic properties and maximal evoked currents. Currents were activated by I H+ regardless of the net charge on the driven substrate, and were independent of Nao+, Ki+ and Clo?, calling into question the familiar concept of the origin of the transporter-mediated current.