Chaperonin GroES

Saibil, H.R. The lid that shapes the pot structure and function of the chaperonin GroES. Structure 4 1-4, 1996. 

One end of GroEL is transiently blocked by the co-chaperonin GroES, an assembly of 10,000-MW subunits. 

The co-chaperonin GroES, containing seven subunits [106], caps the GroEL particle as a dome. A remarkable feature, which has mechanistic implications, is... 

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

The desulfinase enzyme from R. erythropolis IGTS8 and R. erythropolis KA2-5-1 have been isolated and characterized [55,126,163,164] however, the latter enzyme had to be cloned into E. coli, to obtain sufficient enzyme for characterization. Both enzymes have an optimum activity at a temperature of 35°C, but slightly different pH optimum (Table 7). The Km values for HBPSi for the two enzymes were similar but the kcat values were different, probably due to the use of different assays to assess enzyme activity. The fccat values for the IGTS8 enzyme did match closely with that reported by the Gray study [53], Expression of the KA2-5-1 enzyme in E. coli required co-expression of chaperonin genes, groEL/groES. 

Xu Z, Horwich AL, Sigler PB (1997) The crystal structure of the asymmetric GroEL-GroES-(ADP)7 chaperonin complex. Nature 388 741-750... 

Proposed molecular mechanism of GroEL-facilitated reconstitution of oligomeric proteins. Many aspects in this figure such as roles of GroES (chaperonin-10) and ATP remain unclear. See text for details. 

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