Immunogold localization of the DnaK heat shock protein in Escherichia coli cells.
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.
Bukau
B
B
Zentrum für Molekulare Biologie, Universität Heidelberg, FRG.
Reilly
P
P
McCarty
J
J
Walker
G C
GC
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
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C063842:dnaK protein, E coli