PDBsum entry 2k61

Metal binding protein

PDB id: 2k61

Contents

Protein chain

146 a.a. *

Metals

_TB

_CA ×3

* Residue conservation analysis

PDB id:

2k61

Name:

Metal binding protein

Title:

Solution structure of cam complexed to dapk peptide

Structure:

Calmodulin. Chain: a. Synonym: cam. Engineered: yes. Mutation: yes

Source:

Homo sapiens. Man. Organism_taxid: 9606. Gene: calm1, calm, cam, cam1, calm2, cam2, camb, calm3, calml2, cam3, camc, camiii. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

1 models

Authors:

I.Bertini,C.Luchinat,G.Parigi,J.Yuan

Key ref:

I.Bertini et al. (2009). 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. PubMed id: 19317469

Date:

02-Jul-08 Release date: 05-May-09

Protein chain

P0DP23  (CALM1_HUMAN) -  Calmodulin-1 from Homo sapiens

Seq: 149 a.a.

Struc: 146 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

J Am Chem Soc 131:5134-5144 (2009)

PubMed id: 19317469

Accurate solution structures of proteins from X-ray data and a minimal set of NMR data: calmodulin-peptide complexes as examples.

I.Bertini, P.Kursula, C.Luchinat, G.Parigi, J.Vahokoski, M.Wilmanns, J.Yuan.

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.