title: Sphingolipid C4 hydroxylation influences properties of yeast detergent-insoluble glycolipid-enriched membranes.
abstract: Sphingoid base C4 hydroxylation is required for syringomycin E action on the yeast plasma membrane. Detergent-insoluble glycolipid-enriched membranes (DIGs) from a yeast strain lacking C4 hydroxylated sphingoid bases (sur2delta) are composed of linear membrane fragments instead of vesicular structures observed for wild-type DIGs, though they have similar lipid compositions and amounts of DIG marker proteins. Light-scattering bands collected from sur2delta after centrifugation of Triton X-100-treated cell lysates in continuous density gradients have lower buoyant densities than that of the wild-type. The results show that C4 hydroxylation influences the physical and structural properties of DIGs and suggest that syringomycin E interacts with lipid rafts.
authors.affiliation: Department of Biology, Utah State University, Logan, UT 84322-5305, USA.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Idkowiak-Baldys
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Grilley
authors.forename: Jon Y
authors.initials: JY
authors.lastname: Takemoto
mesh_terms: D002458:Cell Fractionation; D002462:Cell Membrane / Q000378:metabolism; D002499:Centrifugation, Density Gradient; D003902:Detergents; D006017:Glycolipids / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000502:physiology*; D012995:Solubility; D013107:Sphingolipids / Q000378:metabolism* / Q000494:pharmacology*
chemical_list: D003902:Detergents; D006017:Glycolipids; D008563:Membrane Lipids; D013107:Sphingolipids