title: Isolation of the stable hexameric DnaK.DnaJ complex from Thermus thermophilus.
abstract: A DnaK homolog (T.DnaK) has been purified as a stable complex with a DnaJ homolog (T.DnaJ) from a thermophilic bacterium, Thermus thermophilus. This complex has an approximate molecular size of 300 kDa and appears to contain three copies of each of T.DnaK and T.DnaJ molecules. Consistently, trigonal ring structures with a diameter (trigonal apex-to-apex) of about 11 nm were observed with electron microscopy. The complex has no endogenously bound AT(D)P and is stable in the presence of Mg-AT(D)P. It possesses a weak ATPase activity and retains about 3 mol of ADP/mole of the complex when incubated with Mg-ATP. This complex is able to interact with the reduced carboxymethylated alpha-lactalbumin which we used as a model unfolded protein.
authors.affiliation: Research Laboratory of Resources Utilization, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Motohashi
authors.forename: H
authors.initials: H
authors.lastname: Taguchi
authors.forename: N
authors.initials: N
authors.lastname: Ishii
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis; D000595:Amino Acid Sequence; D029968:Escherichia coli Proteins; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000648:ultrastructure; D007768:Lactalbumin / Q000378:metabolism; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009711:Nucleotides / Q000378:metabolism; D010316:Particle Size; D011485:Protein Binding; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D016963:Thermus thermophilus / Q000737:chemistry*
chemical_list: C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D046911:Macromolecular Substances; D009711:Nucleotides; D007768:Lactalbumin; D000251:Adenosine Triphosphatases; C063842:dnaK protein, E coli