2eu1

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spinqualitylabelsall models 2eu1, resolution 3.29Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of the chaperonin GroEL-E461K

Overview

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.

About this Structure

2EU1 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

Reference

Crystal structure of the temperature-sensitive and allosteric-defective chaperonin GroELE461K., Cabo-Bilbao A, Spinelli S, Sot B, Agirre J, Mechaly AE, Muga A, Guerin DM, J Struct Biol. 2006 Sep;155(3):482-92. Epub 2006 Jul 8. PMID:16904907

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