IUBMB Enzyme Nomenclature


Accepted name: chaperonin ATPase

Reaction: ATP + H2O + an unfolded polypeptide = ADP + phosphate + a folded polypeptide

Other name(s): chaperonin

Systematic name: ATP phosphohydrolase (polypeptide-unfolding)

Comments: Multisubunit proteins with 2x7 (Type I, in most cells) or 2x8 (Type II, in Archaea) ATP-binding sites involved in maintaining an unfolded polypeptide structure before folding or entry into mitochondria and chloroplasts. Molecular masses of subunits ranges from 10-90 kDa. They are a subclass of molecular chaperones that are related to EC (proteasome ATPase).

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Hemmingsen, S.M., Woolford, C., van der Vies, S.M., Tilly, K., Dennis, D.T., Georgopoulos, G.C., Hendrix, R.W. and Ellis, R.J. Homologous plant and bacterial proteins: chaperone oligomeric protein assembly. Nature 333 (1988) 330-334. [PMID: 2897629]

2. Lubber, T.H., Donaldson, G.K., Viitanen, P.V. and Gatenby, A.A. Several proteins imported into chloroplasts form stable complexes with the GroEL-related chloroplast molecular chaperone. Plant Cell 1 (1989) 1223-1230. [PMID: 2577724]

3. Ellis, R.J. (Ed.), The Chaperonins, Academic Press, San Diego, 1996.

4. Ranson, N.A., White, H.E. and Saibil, H.R. Chaperonins. Biochem. J. 333 (1998) 233-242. [PMID: 9657960]

[EC created 2000 as EC, transferred 2018 to EC]

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