9ZK1 | pdb_00009zk1

Crystal structure of a calcium bound C2 domain containing protein from Trichomonas vaginalis (P21 form)

• PDB DOI: https://doi.org/10.2210/pdb9ZK1/pdb

• Classification: LIPID BINDING PROTEIN
• Organism(s): Trichomonas vaginalis G3
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2025-12-05 Released: 2025-12-17 
• Deposition Author(s): Seattle Structural Genomics Center for Infectious Disease (SSGCID)
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID), National Institutes of Health/Office of the Director

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.51 Å
• R-Value Free: 
  0.214 (Depositor), 0.238 (DCC) 
• R-Value Work: 
  0.188 (Depositor) 
• R-Value Observed: 
  0.189 (Depositor) 

Starting Model: in silico

Literature

Crystal structure of a calcium bound C2 domain containing protein from Trichomonas vaginalis (P21 form)

Liu, L., Lovell, S., Battaile, K.P., Buchko, G.W.

To be published.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Biological Assembly 2  

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

Biological assembly 2 assigned by authors.

Biological Assembly 3  

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

Biological assembly 3 assigned by authors.

Biological Assembly 4  

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

Biological assembly 4 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 66.56 kDa 
• Atom Count: 4,755 
• Modeled Residue Count: 528 
• Deposited Residue Count: 572 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
C2 domain containing protein	A, B, C, D	143	Trichomonas vaginalis G3	Mutation(s): 0  Gene Names: TVAG_002900
UniProt
Find proteins for A2EZR3 (Trichomonas vaginalis (strain ATCC PRA-98 / G3)) Explore A2EZR3  Go to UniProtKB:  A2EZR3

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
1PE	K [auth C]	PENTAETHYLENE GLYCOL C10 H22 O6 JLFNLZLINWHATN-UHFFFAOYSA-N
MES	H [auth B]	2-(N-MORPHOLINO)-ETHANESULFONIC ACID C6 H13 N O4 S SXGZJKUKBWWHRA-UHFFFAOYSA-N
PG4	E [auth A]	TETRAETHYLENE GLYCOL C8 H18 O5 UWHCKJMYHZGTIT-UHFFFAOYSA-N
CA (Subject of Investigation/LOI)	F [auth A], G [auth A], I [auth B], J [auth B], L [auth C], M [auth C], N [auth C], O [auth D], P [auth D], Q [auth D]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.51 Å
• R-Value Free:  0.214 (Depositor), 0.238 (DCC) 
• R-Value Work:  0.188 (Depositor) 
• R-Value Observed: 0.189 (Depositor) 

Diffraction Data: https://doi.org/10.18430/M39ZK1

Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 35.953	α = 90
b = 88.059	β = 90.85
c = 97.198	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
Aimless	data scaling
XDS	data reduction
PHASER	phasing
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-12-17 
Deposition Author(s): Seattle Structural Genomics Center for Infectious Disease (SSGCID)

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	75N93022C00036
National Institutes of Health/Office of the Director	United States	S10OD030394

Revision History  

• Version 1.0: 2025-12-17
  Type: Initial release