Calmodulin (CaM) is a calcium-binding protein which is essential in the regulation of many cellular processes, including inflammation, metabolism, and apoptosis.  Upon calcium binding, CaM undergoes a conformational change which allows for the interaction of binding partners in signaling pathways.  Calmoduphilin, a small molecule that binds to CaM, was discovered using small molecule microarray (SMM) technology.  It binds CaM directly, with a KD of 0.12µM (SPR), and thus can be used to probe the activity of Calmodulin in an in vitro or in vivo biological setting. Barnes-Seeman et al., Angew. Chem. Int. Ed. Engl., 42, 2376-2379, 2003.



Kuboniwa H, Tjandra N, Grzesiek S, Ren H, Klee CB, Bax A.  (1995) Solution structure of calcium free Calmodulin. Nat Struct Biol Sep 2(9):768-76.

PDB: 1cll          

Chattopadhyaya R, Meador WE, Means AR, Quiocho FA.  (1992) Calmodulin structure refined at 1.7A resolution. J Mol Biol    Dec 20; 228(4): 1177-92.

August 2003 Molecule of the Month by Shuchismita Dutta and David Goodsell

doi: 10.2210/rcsb_pdb/mom_2003_8