title: Morphological detection of filipin-sterol complexes in the cytoplasmic membrane of staphylococcal L-form.
abstract: Filipin, a sterol-specific antibiotic, and freeze-fracture electron microscopy were used to study the presence and distribution of sterol in the cytoplasmic membrane of stable staphylococcal L-form cells. Fixed cells were treated with filipin, and then observed by freeze-fracture electron microscopy. Freeze-fractured profiles of the L-form cells treated with filipin demonstrated irregular distribution of protuberances or pits of 25-30 nm, representing filipin-sterol complexes, on the proto-plasmic fracture face (PF) and exoplasmic fracture face (EF) of the cytoplasmic membrane. In contrast, no such structure was detected in the filipin-treated parent cells or protoplasts. The results suggest that some sterol molecules, which are usually not found in staphylococcal or other bacterial cells, emerged on the cytoplasmic membrane after the cells were converted to the stable L-form.
authors.affiliation: Teikyo University, Research Center for Medical Mycology, Tokyo.
authors.forename: Y
authors.initials: Y
authors.lastname: Nishiyama
authors.forename: H
authors.initials: H
authors.lastname: Yamaguchi
mesh_terms: D000935:Antifungal Agents; D002462:Cell Membrane / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D005372:Filipin; D005614:Freeze Fracturing; D011523:Protoplasts / Q000648:ultrastructure; D013211:Staphylococcus aureus / Q000648:ultrastructure*; D013261:Sterols / Q000032:analysis*
chemical_list: D000935:Antifungal Agents; D013261:Sterols; D005372:Filipin