GroEL/GroES Complex

Proteins may make "bad" connections when trying to fold to their native state. These "bad" connectections, or aggregates, can cause the protein to function improperly. Chaperones can prevent and reverse such "bad" connections by binding to and releasing the unfolded or aggregated protein during the folding process. Chaperones do not increase the rate of protein folding, they only increase its efficiency.

GroEL and GroES work together (interact) to help peoteins fold into their native state properly. They do this by surrounding the protein like a cage thereby providing a safe environment for the protein. GroES binds to the top of GroEL and forms a cage around the protein. During this interaction, GroEL undergoes large conformational changes. Pictures of these proteins (obtained from the Protein Data Bank and viewed through RasMol) are shown below.

GroEL/GroES Complex:

Side view
Top view
Bottom view
GroES is the red/orange/yellow top piece. It forms a cap/lid over the top of GroEL. GroEL is made up of two sets of rings (blue/cyan and green/yellow). The unfolded protein would fit inside the cavity of these rings.

GroES, Alone:

Top view
Side view
GroES is shaped like a dome, both when it is alone and when it is bound to GroEL. GroEL, on the other hand, stretches and twists.

GroEL:

Before
After
(Ignore the changes in color.)

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Last updated: 7/13/01