2YEY

Crystal structure of the allosteric-defective chaperonin GroEL E434K mutant

Replaces:  3FBH

Summary for 2YEY

• Entry DOI: 10.2210/pdb2yey/pdb
• Descriptor: 60 KDA CHAPERONIN (1 entity in total)
• Functional Keywords: chaperone, chaperonin, cooperativity, twinning, low-resolution refinement
• Biological source: ESCHERICHIA COLI
• Cellular location: Cytoplasm: P0A6F5
• Total number of polymer chains: 14
• Total formula weight: 773082.41

Authors

Cabo-Bilbao, A.,Mechaly, A.E.,Agirre, J.,Spinelli, S.,Sot, B.,Muga, A.,Guerin, D.M.A. (deposition date: 2011-03-31, release date: 2011-05-18, Last modification date: 2023-12-20)

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 Groele461K.
J.Struct.Biol., 155:482-, 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 (4.5 Å)