The allosteric mechanism of the chaperonin GroEL: A dynamic analysis

AUTOR(ES)

Ma, Jianpeng

FONTE

The National Academy of Sciences

RESUMO

Normal mode calculations on individual subunits and a multisubunit construct are used to analyze the structural transitions that occur during the GroEL cycle. The normal modes demonstrate that the specific displacements of the domains (hinge bending, twisting) observed in the structural studies arise from the intrinsic flexibility of the subunits. The allosteric mechanism (positive cooperativity within a ring, negative cooperativity between rings) is shown to be based on coupled tertiary structural changes, rather than the quaternary transition found in classic allosteric proteins. The results unify static structural data from x-ray crystallography and cryoelectron microscopy with functional measurements of binding and cooperativity.

Documentos Relacionados

• The hydrophobic properties of GroEL: a review of ligand effects on the modulation of GroEL hydrophobic surfaces
• Substrate polypeptide presents a load on the apical domains of the chaperonin GroEL
• Native-like structure of a protein-folding intermediate bound to the chaperonin GroEL
• A polypeptide bound by the chaperonin groEL is localized within a central cavity.
• Nucleotide sequence of rat hsp60 (chaperonin, GroEL homolog) cDNA.