Visualizing the Intermittent Gating of Na+/H+ Antiporters in Single Native Bioluminescent Bacteria**
A previous version of this manuscript has been deposited on a preprint server (https://doi.org/10.1101/2022.07.03.498436).
Graphical Abstract
We report the observation of the intermittent BL blinking of a single bioluminescent bacterium. This study not only demonstrated, for the first time, the intermittent gating dynamics of NhaA antiporters in single native bacteria without any genetic engineering or chemical labeling, but also opened the door for P. phosphoreum to serve as model bacteria for reporting the physiological and metabolic status with spontaneous BL emission.
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.
Conflict of interest
The authors declare no conflict of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
