Calmodulin Structure by X-Ray and NMR

The PDB 3CLN X-ray structure shows a large hydrophobic cleft in each half of the molecule. These hydrophobic regions are believed to represent the sites of interaction with many of the pharmacological agents and target peptides known to bind to cahnoduhn. Some of these will be described below. 

TFP has been widely studied in this regard, and a number of structural studies have indicated the binding of one, two, three, or four TFP molecules to calmodulin in the hydrophobic pockets where target enzymes would also bind. Most studies in solution have indicated that CaM has two high-affinity 

Calmodulin Structure (Source) Method Angle (°) A-B (I-II) Angle (°) C-D (III-IV) Angle (°) E-F (V-VI) Angle (°) G-H (VII-VIII) PDB Entry (Reference Number) 

In 1998, Ovadi and co-workers studied the structure of calmodulin in complexes with two TFP molecules as well as complexes with TFP and two 

GROUP I AND II METALS IN BIOLOGICAL SYSTEMS GROUP II PDB 1A29 

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Calmodulin Structure by X-Ray and NMR. Babu and co-workers published the first X-ray crystallographic structure of Ca " -saturated mammalian calmodulin in 1986 (PDB ascension number 3CLN). As can be seen in Figure 6.21, the molecule is dumbbell-shaped, with an overall length of 65 A. There are two two-EF-hand domains or lobes— N-terminal, residues 5-73 and C-terminal, residues 74-148—connected by a central seven-turn a-helix. The center part of the connecting helix is unwound between residues asp78 and... 

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