PDBsum entry 2lv6

Metal binding protein/transferase

PDB id: 2lv6

Contents

Protein chains

148 a.a.

26 a.a.

Metals

_CA ×4

PDB id:

2lv6

Name:

Metal binding protein/transferase

Title:

The complex between ca-calmodulin and skeletal muscle myosin light chain kinase from combination of nmr and aqueous and contrast-matched saxs data

Structure:

Calmodulin. Chain: a. Synonym: cam. Engineered: yes. Myosin light chain kinase 2, skeletal/cardiac muscle. Chain: b. Fragment: calmodulin-binding residues 566-591. Synonym: mlck2. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: calm1, calm, cam, cam1, calm2, cam2, camb, calm3, calml2, cam3, camc, camiii. Expressed in: escherichia coli. Expression_system_taxid: 511693. Expression_system_variant: codon-plus (de3) ripl. Synthetic: yes.

NMR struc:

1 models

Authors:

A.V.Grishaev,N.J.Anthis,G.M.Clore

Key ref:

A.Grishaev et al. (2012). Contrast-matched small-angle X-ray scattering from a heavy-atom-labeled protein in structure determination: application to a lead-substituted calmodulin-peptide complex. J Am Chem Soc, 134, 14686-14689. PubMed id: 22908850

Date:

29-Jun-12 Release date: 20-Feb-13

Protein chain

P0DP23  (CALM1_HUMAN) -  Calmodulin-1 from Homo sapiens

Seq: 149 a.a.

Struc: 148 a.a.*

Protein chain

Q9H1R3  (MYLK2_HUMAN) -  Myosin light chain kinase 2, skeletal/cardiac muscle from Homo sapiens

Seq: 596 a.a.

Struc: 26 a.a.

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chain B: E.C.2.7.11.18 - [myosin light-chain] kinase.
• Reaction:
  1. L-seryl-[myosin light chain] + ATP = O-phospho-L-seryl-[myosin light chain] + ADP + H⁺
  2. L-threonyl-[myosin light chain] + ATP = O-phospho-L-threonyl-[myosin light chain] + ADP + H⁺
• Cofactor: Ca(2+)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

J Am Chem Soc 134:14686-14689 (2012)

PubMed id: 22908850

Contrast-matched small-angle X-ray scattering from a heavy-atom-labeled protein in structure determination: application to a lead-substituted calmodulin-peptide complex.

A.Grishaev, N.J.Anthis, G.M.Clore.

ABSTRACT

The information content in 1-D solution X-ray scattering profiles is generally restricted to low-resolution shape and size information that, on its own, cannot lead to unique 3-D structures of biological macromolecules comparable to all-atom models derived from X-ray crystallography or NMR spectroscopy. Here we show that contrast-matched X-ray scattering data collected on a protein incorporating specific heavy-atom labels in 65% aqueous sucrose buffer can dramatically enhance the power of conventional small- and wide-angle X-ray scattering (SAXS/WAXS) measurements. Under contrast-matching conditions the protein is effectively invisible and the main contribution to the X-ray scattering intensity arises from the heavy atoms, allowing direct extraction of pairwise distances between them. In combination with conventional aqueous SAXS/WAXS data, supplemented by NMR-derived residual dipolar couplings (RDCs) measured in a weakly aligning medium, we show that it is possible to position protein domains relative to one another within a precision of 1 Å. We demonstrate this approach with respect to the determination of domain positions in a complex between calmodulin, in which the four Ca(2+) ions have been substituted by Pb(2+), and a target peptide. The uniqueness of the resulting solution is established by an exhaustive search over all models compatible with the experimental data, and could not have been achieved using aqueous SAXS and RDC data alone. Moreover, we show that the correct structural solution can be recovered using only contrast-matched SAXS and aqueous SAXS/WAXS data.