1KXP

CRYSTAL STRUCTURE OF HUMAN VITAMIN D-BINDING PROTEIN IN COMPLEX WITH SKELETAL ACTIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structures of the vitamin D-binding protein and its complex with actin: structural basis of the actin-scavenger system.

Otterbein, L.R.Cosio, C.Graceffa, P.Dominguez, R.

(2002) Proc.Natl.Acad.Sci.USA 99: 8003-8008

  • DOI: 10.1073/pnas.122126299
  • Primary Citation of Related Structures:  1KW2

  • PubMed Abstract: 
  • Actin is the most abundant protein in eukaryotic cells, but its release from cells into blood vessels can be lethal, being associated with clinical situations including hepatic necrosis and septic shock. A homeostatic mechanism, termed the actin-scav ...

    Actin is the most abundant protein in eukaryotic cells, but its release from cells into blood vessels can be lethal, being associated with clinical situations including hepatic necrosis and septic shock. A homeostatic mechanism, termed the actin-scavenger system, is responsible for the depolymerization and removal of actin from the circulation. During the first phase of this mechanism, gelsolin severs the actin filaments. In the second phase, the vitamin D-binding protein (DBP) traps the actin monomers, which accelerates their clearance. We have determined the crystal structures of DBP by itself and complexed with actin to 2.1 A resolution. Similar to its homologue serum albumin, DBP consists of three related domains. Yet, in DBP a strikingly different organization of the domains gives rise to a large actin-binding cavity. After complex formation the three domains of DBP move slightly to "clamp" onto actin subdomain 3 and to a lesser extent subdomain 1. Contacts between actin and DBP throughout their extensive 3,454-A(2) intermolecular interface involve a mixture of hydrophobic, electrostatic, and solvent-mediated interactions. The area of actin covered by DBP within the complex approximately equals the sum of those covered by gelsolin and profilin. Moreover, certain interactions of DBP with actin mirror those observed in the actin-gelsolin complex, which may explain how DBP can compete effectively with gelsolin for actin binding. Formation of the strong actin-DBP complex proceeds with limited conformational changes to both proteins, demonstrating how DBP has evolved to become an effective actin-scavenger protein.


    Organizational Affiliation

    Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ACTIN,ALPHA SKELETAL MUSCLE
A
375Oryctolagus cuniculusGene Names: ACTA1 (ACTA)
Find proteins for P68135 (Oryctolagus cuniculus)
Go to Gene View: ACTA1
Go to UniProtKB:  P68135
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
HUMAN VITAMIN D-BINDING PROTEIN
D
458Homo sapiensGene Names: GC
Find proteins for P02774 (Homo sapiens)
Go to Gene View: GC
Go to UniProtKB:  P02774
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download SDF File 
Download CCD File 
A
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.217 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 80.758α = 90.00
b = 87.364β = 90.00
c = 162.686γ = 90.00
Software Package:
Software NamePurpose
CNSphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-06-19
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2013-09-18
    Type: Derived calculations