Heat shock protein substrate binding

Moreover, the thermophilic archaebacterium Sulfolobus shibitae was shown to contain a heat shock protein (TF55) with 40% amino acid sequence identity to mouse TCP-1 (Trent et al., 1991). TF55 formed a double toroid and was able to bind unfolded substrates in vitro, thus strongly implicating it as a functional chaperonin molecule. 

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