Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction | Predict Membrane 

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content

• Total Structure Weight: 36.18 kDa 
• Atom Count: 2267 
• Modelled Residue Count: 299 
• Deposited Residue Count: 330 
• Unique protein chains: 1

6OH2

X-ray crystal structure of the mouse CMP-sialic acid transporter in complex with CMP, by lipidic cubic phase

• PDB DOI: 10.2210/pdb6OH2/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Mus musculus
• Expression System: Komagataella pastoris
• Mutation(s): No 
• Membrane Protein: Yes  PDBTMMemProtMDmpstruc


• Deposited: 2019-04-04 Released: 2019-04-24 
• Deposition Author(s): Ahuja, S., Whorton, M.R.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.58 Å
• R-Value Free: 0.252 
• R-Value Work: 0.241 
• R-Value Observed: 0.241 

Literature

Structural basis for mammalian nucleotide sugar transport.

Ahuja, S., Whorton, M.R.

(2019) Elife 8

• PubMed: 30985278 
• DOI: 10.7554/eLife.45221
• Primary Citation of Related Structures:  
  6OH2, 6OH3, 6OH4


• PubMed Abstract: 
  

Nucleotide-sugar transporters (NSTs) are critical components of the cellular glycosylation machinery. They transport nucleotide-sugar conjugates into the Golgi lumen, where they are used for the glycosylation of proteins and lipids, and they then subsequently transport the nucleotide monophosphate byproduct back to the cytoplasm. Dysregulation of human NSTs causes several debilitating diseases, and NSTs are virulence factors for many pathogens. Here we present the first crystal structures of a mammalian NST, the mouse CMP-sialic acid transporter (mCST), in complex with its physiological substrates CMP and CMP-sialic acid. Detailed visualization of extensive protein-substrate interactions explains the mechanisms governing substrate selectivity. Further structural analysis of mCST's unique lumen-facing partially-occluded conformation, coupled with the characterization of substrate-induced quenching of mCST's intrinsic tryptophan fluorescence, reveals the concerted conformational transitions that occur during substrate transport. These results provide a framework for understanding the effects of disease-causing mutations and the mechanisms of this diverse family of transporters.

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Organizational Affiliation: 

Vollum Institute, Oregon Health & Science University, Portland, United States.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CMP-sialic acid transporter	A	330	Mus musculus	Mutation(s): 0  Gene Names: Slc35a1 Membrane Entity: Yes
UniProt
Find proteins for Q61420 (Mus musculus) Explore Q61420  Go to UniProtKB:  Q61420

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
C5P (Subject of Investigation/LOI)	B [auth A]	CYTIDINE-5'-MONOPHOSPHATE C9 H14 N3 O8 P IERHLVCPSMICTF-XVFCMESISA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.58 Å
• R-Value Free: 0.252 
• R-Value Work: 0.241 
• R-Value Observed: 0.241 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 144.54	α = 90
b = 49.53	β = 107.63
c = 50.15	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
XDS	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2019-04-04 
• Released Date: 2019-04-24 
Deposition Author(s): Ahuja, S., Whorton, M.R.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01GM130909

Revision History  

• Version 1.0: 2019-04-24
  Type: Initial release
  
• Version 1.1: 2020-01-01
  Changes: Author supporting evidence