Membrane rigidity and phosphatidic acid (PtdOH) signal: two important events in Acinetobacter guillouiae SFC 500-1A exposed to Chromium(VI) and phenol

PAULUCCI, N; RACAGNI, G.; GONZALEZ, P; PEPPINO MARGUTTI, M.; VILLASUSO, AL.; FERNANDEZ, M; BIASUTTI, A; AGOSTINI, E

LIPIDS

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2019 vol. 54 p. 557 - 570

0024-4201

The remodeling of membrane lipids is a mechanism that allows microorganisms to survive in unfavorable environments such as industrial effluents, which often containing inorganic and organic pollutants, like chromium and phenol. In the present work, we evaluated the effect of Cr(VI) and phenol on the membrane of A. guillouiae SFC 500-1A, a bacterial strain isolated from tannery sediments which often contain such pollutants, among others. The presence of lipid kinases and phospholipases and the changes in their activities under exposure to these pollutants were determined. Cr(VI) and Cr(VI)+phenol exert a rigidity effect on the A. guillouiae SFC 500-1A membrane, which was maintained until 16 h. This effect would be attributed to(cambiar) an increase of cardiolipin (Ptd2Gro) and a decrease of phosphatidylethanolamine (PtdEtn) suggesting more order and rigidity in the membranes. An increased phospholipase A activity (PLA, EC 3.1.1.4) could be responsible of the decrease in PtdEtn levels. Moreover, the results indicate that Cr(VI) and Cr(VI)+phenol trigger the phosphatidic acid (PtdOH) signal, possibly via phospholipases, due to significantly increased phosphatidylinositol 4-phosphate (PtdIns-4-P) levels. This report provides the first evidences that A. guillouiae SFC 500-1A is capable of sensing Cr(VI) and phenol, transducing this signal through changes in membrane physic state and triggering minor lipid signalling events.