Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Protein Workshop | Ligand Explorer

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 23239.00 
• Atom Count: 1266 
• Residue Count: 199 
• Unique protein chains: 1

4N5X

Crystal structure of N-terminal calmodulin-like Calcium sensor of human mitochondrial ATP-Mg/Pi carrier SCaMC1

• DOI: 10.2210/pdb4N5X/pdb

• Classification: CALCIUM-BINDING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): 1 


• Deposited: 2013-10-10 Released: 2013-12-18 
• Deposition Author(s): Yang, Q., Bruschweiler, S., Chou, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.1 Å
• R-Value Free: 0.225 
• R-Value Work: 0.177 

Literature

A Self-Sequestered Calmodulin-like Ca(2+) Sensor of Mitochondrial SCaMC Carrier and Its Implication to Ca(2+)-Dependent ATP-Mg/Pi Transport.

Yang, Q., Bruschweiler, S., Chou, J.J.

(2014) Structure 22: 209-217

• PubMed: 24332718 
• DOI: 10.1016/j.str.2013.10.018


• PubMed Abstract: 
  

The mitochondrial carriers play essential roles in energy metabolism. The short Ca²⁺-binding mitochondrial carrier (SCaMC) transports ATP-Mg in exchange for Pi and is important for activities that depend on adenine nucleotides. SCaMC adopts, in addition to the transmembrane domain (TMD) that transports solutes, an extramembrane N-terminal domain (NTD) that regulates solute transport in a Ca²⁺-dependent manner. Crystal structure of the Ca²⁺-bound NTD reveals a compact architecture in which the functional EF hands are sequestered by an endogenous helical segment. Nuclear magnetic resonance (NMR) relaxation rates indicated that removal of Ca²⁺ from NTD results in a major conformational switch from the rigid and compact Ca²⁺-bound state to the dynamic and loose apo state. Finally, we showed using surface plasmon resonance and NMR titration experiments that free apo NTDs could specifically interact with liposome-incorporated TMD, but that Ca²⁺ binding drastically weakened the interaction. Our results together provide a molecular explanation for Ca²⁺-dependent ATP-Mg flux in mitochondria.

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Organizational Affiliation: 

Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Calcium-binding mitochondrial carrier protein SCaMC-1	A	199	Homo sapiens	Mutation(s): 1  Gene Names: SLC25A24 (APC1, MCSC1, SCAMC1)
Find proteins for Q6NUK1 (Homo sapiens) Go to Gene View: SLC25A24 Go to UniProtKB:  Q6NUK1

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
CA	A	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N
PEG	A	DI(HYDROXYETHYL)ETHER C4 H10 O3 MTHSVFCYNBDYFN-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.1 Å
• R-Value Free: 0.225 
• R-Value Work: 0.177 
• Space Group: P 3₁ 2 1

Unit Cell:

Length (Å)	Angle (°)
a = 51.210	α = 90.00
b = 51.210	β = 90.00
c = 112.153	γ = 120.00

Software Package:

Software Name	Purpose
HKL-2000	data scaling
PHASER	phasing
HKL-2000	data collection
HKL-2000	data reduction
PHENIX	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-10-10 
• Released Date: 2013-12-18 
• Deposition Author(s): Yang, Q., Bruschweiler, S., Chou, J.

Revision History 

• Version 1.0: 2013-12-18
  Type: Initial release
• Version 1.1: 2014-02-26
  Type: Database references
• Version 1.2: 2018-06-13
  Type: Data collection