GroES protein

How does the GroEL-GroES complex function as a chaperone to assist protein folding Although several aspects of the mechanism are not clear, the main features of the functional cycle are known. The first step is the... 

Chen, S. et al. Eocation of a folding protein and shape changes in GroEL-GroES complexes imaged by cryo-electron microscopy. Nature 371 261-264, 1994. 

Mayhew, M., et al. Protein folding in the central cavity of the GroEE-GroES chaperonin complex. Nature 379 420-426, 1996. 

It is generally believed that energy-independent chaperones are unable to allow refolding of non-native proteins. They bind to hydrophobic surfaces of denatured proteins to prevent aggregation and pass them to energy-dependent chaperones such as the DnaK or the GroE chaperone machines. 

Fig. 10.6 [ N. HJ-TROSY spectrum and [15N,n H]-CRIPT-TROSY spectrum of uniformly 15N, -labeled GroES bound to SRI with a molecular weight of 480 kDa. GroES is a homo-heptameric protein with a molecular weight 78 kDa, and SRI is a homoheptameric single ring variant of GroEL with a molecular weight 400 kDa. The cross peaks observed in the [15N, HJ-TROSYspectrum are...

Unfolded protein binds to the GroEL pocket not blocked by GroES. 

Within the GroEL-GroES cage polypeptide chains can fold without becoming entangled with other proteins or being cleaved by protein-hydrolyzing enzymes... 

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