Crystal structure of the temperature-sensitive and allosteric-defective chaperonin GroEL(E461K).Cabo-Bilbao, A., Spinelli, S., Sot, B., Agirre, J., Mechaly, A.E., Muga, A., Guerin, D.M.A.
(2006) J.Struct.Biol. 155: 482-492
- PubMed: 16904907
- DOI: 10.1016/j.jsb.2006.06.008
- Primary Citation of Related Structures:
- PubMed Abstract:
- Ionic interactions at both inter-ring contact sites of GroEL are involved in transmission of the allosteric signal: a time-resolved infrared difference study
Sot, B.,von Germar, F.,Mantele, W.,Valpuesta, J.M.,Taneva, S.G.,Muga, A.
(2005) Protein Sci. 14: 2267
- A mutant chaperonin with rearranged inter-ring electrostatic contacts and temperature-sensitive dissociation
Sewell, B.T.,Best, R.B.,Chen, S.,Roseman, A.M.,Farr, G.W.,Horwich, A.L.,Saibil, H.R.
(2004) Nat.Struct.Mol.Biol. 11: 1128
- The crystal structure of the asymmetric GroEL-GroES-(ADP)7 chaperonin complex
Xu, Z.,Horwich, A.L.,Sigler, P.B.
(1997) Nature 388: 741
- Conformational variability in the refined structure of the chaperonin GroEL at 2.8 A resolution
Braig, K.,Adams, P.D.,Brunger, A.T.
(1995) Nature 2: 1083
- Crystal structure of wild-type chaperonin GROEL
Bartolucci, C.,Lamba, D.,Grazulis, S.,Manakova, E.,Heumann, H.
(2005) J.Mol.Biol. 354: 940
- GroEL stability and function. Contribution of the ionic interactions at the inter-ring contact sites
Sot, B.,Banuelos, S.,Valpuesta, J.M.,Muga, A.
(2003) J.Biol.Chem. 278: 32083
- Salt bridges at the inter-ring interface regulate the thermostat of GroEL
Sot, B.,Galan, A.,Valpuesta, J.M.,Bertrand, S.,Muga, A.
(2002) J.Biol.Chem. 277: 34024
The chaperonin GroEL adopts a double-ring structure with various modes of allosteric communication. The simultaneous positive intra-ring and negative inter-ring co-operativities alternate the functionality of the folding cavities in both protein ring ...
The chaperonin GroEL adopts a double-ring structure with various modes of allosteric communication. The simultaneous positive intra-ring and negative inter-ring co-operativities alternate the functionality of the folding cavities in both protein rings. Negative inter-ring co-operativity is maintained through different inter-ring interactions, including a salt bridge involving Glu 461. Replacement of this residue by Lys modifies the temperature sensitivity of the substrate-folding activity of this protein, most likely as a result of the loss of inter-ring co-operativity. The crystal structure of the mutant chaperonin GroELE461K has been determined at 3.3A and compared with other structures: the wild-type GroEL, an allosteric defective GroEL double mutant and the GroEL-GroES-(ADP)7 complex. The inter-ring region of the mutant exhibits the following characteristics: (i) no salt-bridge stabilizes the inter-ring interface; (ii) the mutated residue plays a central role in defining the relative ring rotation (of about 22 degrees) around the 7-fold axis; (iii) an increase in the inter-ring distance and solvent accessibility of the inter-ring interface; and (iv) a 2-fold reduction in the stabilization energy of the inter-ring interface, due to the modification of inter-ring interactions. These characteristics explain how the thermal sensitivity of the protein's fundamental properties permits GroEL to distinguish physiological (37 degrees C) from stress (42 degrees C) temperatures.
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