PDBsum entry 1ij6

Metal binding protein

PDB id: 1ij6

Contents

Protein chain

305 a.a. *

Metals

_CA ×4

* Residue conservation analysis

PDB id:

1ij6

Name:

Metal binding protein

Title:

Ca2+-bound structure of multidomain ef-hand protein, cbp40, from true slime mold

Structure:

Plasmodial specific lav1-2 protein. Chain: a. Fragment: residues 33-355. Engineered: yes

Source:

Physarum polycephalum. Organism_taxid: 5791. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

3.10Å R-factor: 0.249 R-free: 0.293

Authors:

W.Iwasaki,H.Sasaki,A.Nakamura,K.Kohama,M.Tanokura

Key ref:

W.Iwasaki et al. (2003). Metal-free and Ca2+-bound structures of a multidomain EF-hand protein, CBP40, from the lower eukaryote Physarum polycephalum. Structure, 11, 75-85. PubMed id: 12517342 DOI: 10.1016/S0969-2126(02)00932-2

Date:

25-Apr-01 Release date: 11-Feb-03

Protein chain

P14725  (LAV1_PHYPO) -  Plasmodial-specific protein LAV1-2 from Physarum polycephalum

Seq: 355 a.a.

Struc: 305 a.a.

DOI no: 10.1016/S0969-2126(02)00932-2

Structure 11:75-85 (2003)

PubMed id: 12517342

Metal-free and Ca2+-bound structures of a multidomain EF-hand protein, CBP40, from the lower eukaryote Physarum polycephalum.

W.Iwasaki, H.Sasaki, A.Nakamura, K.Kohama, M.Tanokura.

ABSTRACT

Acellular slime mold, Physarum polycephalum, has a unique wound-healing system. When cytoplasm of plasmodia is exposed to extracellular fluid, calcium binding protein 40 (CBP40) seals damaged areas, forming large aggregates Ca(2+) dependently. Part of the CBP40 is truncated at the N terminus by a proteinase in plasmodia (CBP40delta), which does not aggregate in the Ca(2+)-bound form. Here we report the crystal structures of CBP40delta in both the metal-free and the Ca(2+)-bound states. Both structures consist of three domains: coiled-coil, intervening, and EF-hand. The topology of the EF-hand domain is similar to that of calpain. The N-terminal half of CBP40Delta interacts with the C-terminal EF-hands through a large hydrophobic interface, necessary for high Ca(2+) affinity. Conformational change upon Ca(2+) binding is small; however, the structure of CBP40delta provides novel insights into the mechanism of Ca(2+)-dependent oligomerization.

Selected figure(s)

Figure 6.
Figure 6. Comparison of the Interhelical Angles between the E and F Helices of EF-HandsThe metal-free and Ca^2+-bound forms of CBP40D are shown in yellow and white, respectively. EF3 of Ca^2+-bound calmodulin in the open form is colored in green, and that of Ca^2+-free calmodulin in the closed form is in red. The Ca^2+ ions are represented as spheres in the respective backbone colors.

The above figure is reprinted by permission from Cell Press: Structure (2003, 11, 75-85) copyright 2003.

Figure was selected by an automated process.