PDBsum entry 1tlk

Calmodulin-binding

PDB id: 1tlk

Contents

Protein chain

103 a.a. *

Waters ×31

* Residue conservation analysis

PDB id:

1tlk

Name:

Calmodulin-binding

Title:

X-ray structure determination of telokin, thE C-terminal domain of myosin light chain kinase, at 2.8 angstroms resolution

Structure:

Telokin. Chain: a. Engineered: yes

Source:

Meleagris gallopavo. Turkey. Organism_taxid: 9103

Biol. unit:

Dimer (from PQS)

Resolution:

2.80Å R-factor: 0.184

Authors:

H.M.Holden,I.Rayment

Key ref:

H.M.Holden et al. (1992). X-ray structure determination of telokin, the C-terminal domain of myosin light chain kinase, at 2.8 A resolution. J Mol Biol, 227, 840-851. PubMed id: 1404391 DOI: 10.1016/0022-2836(92)90226-A

Date:

20-Jul-92 Release date: 31-Oct-93

Protein chain

P56276  (MYLK_MELGA) -  Telokin from Meleagris gallopavo

Seq: 154 a.a.

Struc: 103 a.a.

Enzyme reactions

• Enzyme class: E.C.2.7.1.117 - Transferred entry: 2.7.11.18.
• Reaction: ATP + [myosin light-chain] = ADP + [myosin light-chain] phosphate
• Cofactor: Calcium

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

Added reference

DOI no: 10.1016/0022-2836(92)90226-A

J Mol Biol 227:840-851 (1992)

PubMed id: 1404391

X-ray structure determination of telokin, the C-terminal domain of myosin light chain kinase, at 2.8 A resolution.

H.M.Holden, M.Ito, D.J.Hartshorne, I.Rayment.

ABSTRACT

The three-dimensional structure of telokin, an acidic protein identical to the C-terminal portion of smooth muscle myosin light chain kinase from turkey gizzard, has been determined at 2.8 A resolution and refined to a crystallographic R-factor of 19.5% for all measured X-ray data from 30 A to 2.8 A. Crystals used in the investigation belonged to the space group P3(2)21, with one molecule per asymmetric unit and unit cell dimensions of a = b = 64.4 A and c = 50.6 A. Telokin contains 154 amino acid residues, 103 of which were visible in the electron density map. The overall molecular fold of telokin consists of seven strands of antiparallel beta-pleated sheet that wrap around to form a barrel. There is also an extended tail of eight amino acid residues at the N terminus that does not participate in beta-sheet formation. The beta-barrel can be simply envisioned as two layers of beta-sheet, nearly parallel to one another, with one layer containing four and the other three beta-strands. This type of beta-barrel, as seen in telokin, was first observed for the CH2 domain of an immunoglobulin fragment Fc. Telokin is an intracellular protein and, as such, does not contain the disulphide linkage between beta-strands B and F normally observed in the immunoglobulin constant domains. It does, however, contain two cysteine amino acid residues (Cys63 and Cys115) that are situated at structurally identical positions to those forming the disulphide linkage in the immunoglobulin constant domain.

Selected figure(s)

Figure 1.
Figure 1. Schematic representation of the rrangement of regulatory and functional domains in smooth muscle yosin light chain kinase based on genetic and biochemical studies (Olsen et al., 1990) ad their relationship to telokin. The Figure shows the positins of the immunoglobuin-like sequence motifs types I and II) that are omologous to those observed in twitchin (Benian et al., 1989). t also ives the location in the sequnce of the catalytic and calmodulin binding domains (CAM). The segmen responsible for auto-inhibition o MLCK is ocated between residues 786 and 805 and overaps the calmodulin binding region (Ito et al., 1991).

Figure 10.
Figure 10. Superpsition of telokin and PapD. The superposition shown was generated as described for Fig. 7. X-ray co-ordinates for the PapD molecule were graciousl supplied by Dr Carl Briinden. Telokin and PapD are shown in continuous nd open bonds, respectivel.

The above figures are reprinted by permission from Elsevier: J Mol Biol (1992, 227, 840-851) copyright 1992.

Figures were selected by an automated process.