Start Publications Hopanoids, like sterols, modulate dynamics, compaction, phase ...
KSV NIMA

Hopanoids, like sterols, modulate dynamics, compaction, phase segregation and permeability of membranes

Year: 2019

Journal: Biochim. Biophys. Acta-Biomembr., Volume 1861, DEC 1

Authors: Mangiarotti, Agustin; Genovese, Dario M.; Naumann, Christoph A.; Monti, Mariela R.; Wilke, Natalia

Organizations: SeCyT-UNC, ArgentinaSecretaria de Ciencia y Tecnologia (SECYT); CONICET, ArgentinaConsejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET); FonCyT, ArgentinaFONCyT [PICT 2015-0662]; Ministry of Education of Argentina; Fulbright Commission

Keywords: Diplopterol; Liquid-ordered phase; Membrane rheology; Membrane permeability; Bacterial survival

In recent years, hopanoids, a group of pentacyclic compounds found in bacterial membranes, are in the spotlight since it was proposed that they induce order in lipid membranes in a similar way cholesterol do in eukaryotes, despite their structural differences. We studied here whether diplopterol (an abundant hopanoid) promoted similar effects on model membranes as sterols do. We analyzed the compaction, dynamics, phase segregation, permeability and compressibility of model membranes containing diplopterol, and compared with those containing sterols from animals, plants and fungi. We also tested the effect that the incubation with diplopterol had on hopanoid-lacking bacteria. Our results show that diplopterol induces phase segregation, increases lipid compaction, and decreases permeability on phospholipid membranes, while retaining membrane fluidity and compressibility. Furthermore, the exposition to this hopanoid decreases the permeability of the opportunistic pathogen Pseudomonas aeruginosa and increases the resistance to antibiotics. All effects promoted by diplopterol were similar to those generated by the sterols. Our observations add information on the functional significance of hopanoids as molecules that play an important role in membrane organization and dynamics in model membranes and in a bacterial system.