Figure 1.

Schematic illustration of the basic concept of the gA-based assay employed to monitor PLD activity (41). Enzymatic activity of PLD (green) on a planar lipid bilayer composed of electrically neutral PC lipids (gray) results in production of negatively charged PA lipids (red); the concomitant accumulation of cations (light blue spheres) near the membrane surface leads to an increase in single-channel conductance, γ, of transient openings of gA pores. The schematic current-versus-time traces below the cartoons depict the PLD-induced increase in the ion current passing through single gA channels.