Interfacial behaviour of diacylglycerol pyrophosphate and their mixtures with phosphatidic acid in response to pH and Zn2+

A. L. VILLASUSO, N. WILKE, B MAGGIO, E MACHADO

Frontiers in Plant Science

Frontiers Editorial Office

Lugar: Lausanne; Año: 2014

iacylglycerol pyrophosphate (DGPP) is a minor lipid that attenuates the phosphatidic acid (PA) signal, and also DGPP itself would be a signaling lipid. DGPP is an anionic phospholipid with a pyrophosphate group attached to diacylglycerol that was shown to respond to changes of pH, thus affecting the surface organization of DGPP and their interaction with PA. In this work, we have investigated how the presence of Zn2+, modulates the surface organization of DGPP and its interaction with PA at acid and basic pHs. Both lipids formed expanded monolayers at pH 5 and 8. At pH 5, monolayers formed by DGPP became stiffer when Zn2+was added to the subphase,  while the surface potential decreased. At this pH, Zn2+ induced a phase transition from an expanded to a condensed phase state in monolayers formed by PA. Conversely, at pH 8 the effects induced by the presence of Zn2+ on the surface behaviors of the pure lipids were smaller. Thus, the interaction of the bivalent cation with both lipid