Figure 15.22. Conformational Changes in Calmodulin on Calcium Binding.

Figure 15.22Conformational Changes in Calmodulin on Calcium Binding

Figure 15.22. Conformational Changes in Calmodulin on Calcium Binding. In the absence of calcium (top), the EF hands have hydrophobic cores. On binding of a calcium ion (green sphere) to each EF hand, structural changes expose hydrophobic patches on the calmodulin surface. These patches serve as docking regions for target proteins. Acidic residues are shown in red, basic residues in blue, and hydrophobic residues in black. The central helix in calmodulin remains somewhat flexible, even in the calcium-bound state.

From: Section 15.3, Calcium Ion Is a Ubiquitous Cytosolic Messenger

Cover of Biochemistry
Biochemistry. 5th edition.
Berg JM, Tymoczko JL, Stryer L.
New York: W H Freeman; 2002.
Copyright © 2002, W. H. Freeman and Company.

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