Related Experiment Video
Updated: Jul 17, 2026

Reconstitution of the Bacterial Glutamate Receptor Channel by Encapsulation of a Cell-Free Expression System
Published on: March 8, 2024
Effects of divalent cations on encapsulation and release in the GroEL-assisted folding
Hiroshi Okuda1, Chihaya Sakuhana, Risa Yamamoto
1Department of Applied Biological Chemistry, School of Agriculture, Kinki University, 3327-204, Nakamachi, Nara, 631-8505, Japan.
Abstract:
Chaperonin GroEL assists protein folding in the presence of ATP and magnesium. Recent studies have shown that several divalent cations other than magnesium induce conformational changes of GroEL, thereby influencing chaperonin-assisted protein folding, but little is known about the detailed mechanism for such actions. Thus, the effects of divalent cations on protein encapsulation by GroEL/ES complexes were investigated. Of the divalent cations, not only magnesium, but also manganese ions enabled the functional refolding and release of 5,10-methylenetetrahydroforate reductase (METF) by GroEL. Neither ATP hydrolysis nor METF refolding was observed in the presence of zinc ion, whereas only ATP hydrolysis was induced by cobalt and nickel ions. SDS-PAGE and gel filtration analyses revealed that cobalt, nickel and zinc ions permit the formation of stable substrate-GroEL-GroES cis-ternary complexes, but prevent the release of METF from GroEL.
Related Concept Videos
Pinching-off of Coated Vesicles
Complexation Equilibria: The Chelate Effect
Protein Folding
COP Coated Vesicles
Protein Folding Quality Check in the RER
Transport Across the Golgi

