title: Properties of the chaperonin complex from the halophilic archaeon Haloferax volcanii.
abstract: The halophilic archaeon Haloferax volcanii has three genes encoding type II chaperonins, named cct1, cct2 and cct3. We show here that the three CCT proteins are all expressed but not to the same level. All three proteins are further induced on heat shock. The CCT proteins were purified by ammonium sulphate precipitation, sucrose gradient centrifugation and hydrophobic interaction chromatography. This procedure yields a high molecular mass complex (or complexes). The complex has ATPase activity, which is magnesium dependent, low salt-sensitive and stable to at least 75 degrees C. Activity requires high levels of potassium ions and was reduced in the presence of an increasing concentration of sodium ions.
authors.affiliation: School of Biosciences, University of Birmingham, B15 2TT, Birmingham, UK.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Large
authors.forename: Eszter
authors.initials: E
authors.lastname: Kovacs
authors.forename: Peter A
authors.initials: PA
authors.lastname: Lund
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000645:Ammonium Sulfate / Q000494:pharmacology; D002499:Centrifugation, Density Gradient; D018833:Chaperonins / Q000737:chemistry* / Q000302:isolation & purification; D002845:Chromatography; D004247:DNA / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D019622:Haloferax volcanii / Q000378:metabolism*; D006358:Hot Temperature; D008274:Magnesium / Q000494:pharmacology; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D011485:Protein Binding; D012964:Sodium / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology; D013395:Sucrose / Q000494:pharmacology; D013696:Temperature
chemical_list: D012965:Sodium Chloride; D013395:Sucrose; D011189:Potassium Chloride; D004247:DNA; D012964:Sodium; D000251:Adenosine Triphosphatases; D018833:Chaperonins; D008274:Magnesium; D000645:Ammonium Sulfate