Visualizing the Intermittent Gating of Na<sup>+</sup>/H<sup>+</sup> Antiporters in Single Native Bioluminescent Bacteria**
Yaohua Li, Haoran Li, Jia Gao, Ben Niu, Huan Wang, Wei Wang
Abstract
Abstract While the intermittent gating of ion channels has been well studied for decades, dynamics of the action of secondary transporters, another major pathway for ion transmembrane transports, remains largely unexplored in living cells. Herein, intermittent blinking of the spontaneous bioluminescence (BL) from single native bacteria, P. phosphoreum , was reported, investigated and attributed to the intermittent gating of sodium/proton antiporters (NhaA) between the active and inactive conformations. Each gating event caused the rapid depolarization and recovery of membrane potential within several seconds, accompanying with the apparent BL blinking due to the transient inhibitions on the activity of the respiratory chain. Temperature‐dependent measurements further obtained an activation energy barrier of the conformational change of 20.3 kJ mol −1 .