Multivalent binding of nonnative substrate proteins by the chaperonin GroEL

Article Abstract:

Many nonnative proteins bind to more than one of the seven apical domains of the GroEL chaperonin ring. Chaperonins are proteins that facilitate the folding of nonnative proteins.

ATP-bound states of GroEL captured by cryo-electron microscopy

Article Abstract:

The conformational changes due to ATP binding to the chaperonin GroEL protein are examined using a mutant enzyme complexed with ATP. Results show that ATP binding changes the interaction pattern through the entire double ring structure.

United Kingdom, Physiological aspects, Structure-activity relationships (Biochemistry)

GroEL-GroES cycling: ATP and nonnative polypeptide direct alternation of folding-active rings

Article Abstract:

A study using cryon-electron microscopy and atomic structure fitting was conducted to better understand the cycling system of the Escherichia coli chaperonin called GroEL and cochaperonin GroES. Results revealed that the two rings of chaperonin, GroES and adenosine triphosphate, function in coordinated and directional manner in the presence of nonnative substrate. It was also found that the GroES directly alternates its rings with the formation of new cis-ternary complexes.

Usage, Escherichia coli, Electron microscopy, Polypeptides