2K61

Solution structure of CaM complexed to DAPk peptide

Summary for 2K61

• Entry DOI: 10.2210/pdb2k61/pdb
• NMR Information: BMRB: 7423,7424,7425,15852
• Descriptor: Calmodulin, CALCIUM ION, TERBIUM(III) ION (3 entities in total)
• Functional Keywords: calmodulin, dapk peptide, methylation, phosphoprotein, metal binding protein
• Biological source: Homo sapiens (man)
• Cellular location: Cytoplasm, cytoskeleton, spindle : P62158
• Total number of polymer chains: 1
• Total formula weight: 17001.49

Authors

Bertini, I.,Luchinat, C.,Parigi, G.,Yuan, J. (deposition date: 2008-07-02, release date: 2009-05-05, Last modification date: 2024-05-08)

Primary citation

Bertini, I.,Kursula, P.,Luchinat, C.,Parigi, G.,Vahokoski, J.,Wilmanns, M.,Yuan, J.
Accurate solution structures of proteins from X-ray data and a minimal set of NMR data: calmodulin-peptide complexes as examples.
J.Am.Chem.Soc., 131:5134-5144, 2009

PubMed Abstract: A strategy for the accurate determination of protein solution structures starting from X-ray data and a minimal set of NMR data is proposed and successfully applied to two complexes of calmodulin (CaM) with target peptides not previously described. Its implementation in the present case is based on the use of lanthanide ions as substitutes for calcium in one of the four calcium binding sites of CaM and the collection of pseudocontact shift (pcs) and residual dipolar coupling (rdc) restraints induced by the paramagnetic metals. Starting from the crystal structures, new structural models are calculated that are in excellent agreement with the paramagnetic restraints and differ significantly from the starting crystal structures. In particular, in both complexes, a change in orientation of the first helix of the N-terminal CaM domain and of the whole C-terminal domain is observed. The simultaneous use of paramagnetic pcs and rdc restraints has the following crucial advantages: (i) it allows one to assess the possible presence of interdomain conformational freedom, which cannot be detected if the rdc values are derived from external orienting media; (ii) in the absence of significant conformational freedom, the global orientation tensor can be independently and precisely determined from pcs values, which are less sensitive than rdc values to the presence of local structural inaccuracies, and therefore (iii) the relative rearrangement of a domain or a secondary structure element with respect to the metal-bearing domain can be detected.

PubMed: 19317469
DOI: 10.1021/ja8080764

Experimental method

SOLUTION NMR