title: Immunogold localization of the DnaK heat shock protein in Escherichia coli cells.
abstract: Previously reported cell fractionation experiments have yielded conflicting information on the cellular localization of the DnaK heat shock protein of Escherichia coli. Here we used immunogold labelling of ultra-thin sections to determine the localization of DnaK in unstressed cells at 30 degrees C as well as in heat-shocked cells. In cells grown at 30 degrees C, gold particles were found predominantly in the cytoplasm, indicating that the majority of the DnaK molecules are cytoplasmic; however, a fraction of the gold particles was located in proximity to the membranes, raising the possibility that a subpopulation of DnaK proteins is membrane-associated. Heat shock of the cells did not induce detectable relocalization of DnaK.
authors.affiliation: Zentrum für Molekulare Biologie, Universität Heidelberg, FRG.
authors.forename: B
authors.initials: B
authors.lastname: Bukau
authors.forename: P
authors.initials: P
authors.lastname: Reilly
authors.forename: J
authors.initials: J
authors.lastname: McCarty
authors.forename: G C
authors.initials: GC
authors.lastname: Walker
mesh_terms: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins / Q000276:immunology / Q000302:isolation & purification*; D002451:Cell Compartmentation; D004926:Escherichia coli / Q000737:chemistry / Q000648:ultrastructure*; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000276:immunology / Q000302:isolation & purification*; D007150:Immunohistochemistry; D009154:Mutation
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C063842:dnaK protein, E coli