The unique chaperone operon of Thermotoga maritima: cloning and initial characterization of a functional Hsp70 and small heat shock protein.
The hyperthermophilic eubacterium Thermotoga maritima possesses an operon encoding an Hsp70 molecular chaperone protein and a protein with meaningful homology to the small heat shock protein family of chaperones. This represents the first demonstrated co-operon organization for these two important classes of molecular chaperones. We have cloned and initially characterized these proteins as functional chaperones in vitro: the Hsp70 is capable of ATP hydrolysis and substrate binding, and the small heat shock protein can suppress protein aggregation and stably bind a refolding-competent substrate. In addition, the primary sequence of the Hsp70 is used to infer the phylogenetic relationships of T. maritima, one of the deepest-branching eubacteria known.
Michelini
E T
ET
Institute of Molecular Biology and Department of Chemistry, University of Oregon, Eugene, Oregon 97403, USA.
Flynn
G C
GC
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D009876:Operon / Q000235:genetics*; D010455:Peptides / Q000378:metabolism; D010802:Phylogeny; D020124:Thermotoga maritima / Q000235:genetics* / Q000378:metabolism
D004269:DNA, Bacterial; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D010455:Peptides; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases