Membrane bilayer properties of sphingomyelins with amide-linked 2- or 3-hydroxylated fatty acids

► Acyl chain-hydroxylated sphingomyelins (SM) exist in specialized tissues and cells, and their biophysical and sterol-interacting properties were examined. ► It was clearly observed that 2-hydroxylation stabilized SM interactions, whereas 3-hydroxylation destabilized, irrespective of chain length. ► Sterol interaction with both 2- and 3-hydroxylated SM analogs was attenuated compared to nonhydroxylated SM. ► We conclude that hydroxylation in the SM interfacial region markedly affects intermolecular interactions and SM/sterol association.