title: Isolation, purification and some ultrastructural details of discharged ejectisomes of cryptophytes.
abstract: The first successful isolation of discharged ejectisomes from pigmented cryptophytes is reported. Discharged ejectisomes from a Chroomonas and two Cryptomonas species were characterized by transmission electron microscopy using negative staining and freeze-etching. Tubular-shaped fragments of variable lengths and diameters were obtained which showed a paracrystalline lattice. Particle periodicities of 4.1 nm along the longitudinal axis and 3.1 nm in the transverse direction were measured in negative-stained fragments. The dimensions measured from freeze-etched ejectisome fragments were about 0.5-1 nm larger. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed a protein banding pattern, dominated by polypeptides of 40-44, 23-25 and 16-18 kDa. The results are discussed in the context of what is currently known about extrusomes of protists.
authors.affiliation: Planktologie, ICBM, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany. erhard.rhiel@uni-oldenburg.de
authors.forename: Erhard
authors.initials: E
authors.lastname: Rhiel
authors.forename: Martin
authors.initials: M
authors.lastname: Westermann
mesh_terms: D002458:Cell Fractionation / Q000379:methods*; D002468:Cell Physiological Phenomena; D044785:Cryptophyta / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D005613:Freeze Etching; D046529:Microscopy, Electron, Transmission; D015388:Organelles / Q000737:chemistry* / Q000648:ultrastructure*; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification; D013045:Species Specificity; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D010455:Peptides