2EU1

Crystal structure of the chaperonin GroEL-E461K

Summary for 2EU1

• Entry DOI: 10.2210/pdb2eu1/pdb
• Related: 1AON 1GRL 1OEL 1XCK
• Descriptor: GROEL (1 entity in total)
• Functional Keywords: chaperonin, groel, hsp60, e461k, chaperone-peptide binding protein complex, chaperone/peptide binding protein
• Biological source: Escherichia coli
• Cellular location: Cytoplasm : P0A6F5
• Total number of polymer chains: 14
• Total formula weight: 803484.82

Authors

Cabo-Bilbao, A.,Spinelli, S.,Sot, B.,Agirre, J.,Mechaly, A.E.,Muga, A.,Guerin, D.M.A. (deposition date: 2005-10-28, release date: 2006-08-29, Last modification date: 2023-08-23)

Primary citation

Cabo-Bilbao, A.,Spinelli, S.,Sot, B.,Agirre, J.,Mechaly, A.E.,Muga, A.,Guerin, D.M.A.
Crystal structure of the temperature-sensitive and allosteric-defective chaperonin GroEL(E461K).
J.Struct.Biol., 155:482-492, 2006

PubMed Abstract: 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.

PubMed: 16904907
DOI: 10.1016/j.jsb.2006.06.008

Experimental method

X-RAY DIFFRACTION (3.29 Å)