9NT3 | pdb_00009nt3

Crystal structure of apo ecLacI transcription factor ancestor 1

• PDB DOI: https://doi.org/10.2210/pdb9NT3/pdb

• Classification: TRANSCRIPTION
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2025-03-18 Released: 2025-06-18 
• Deposition Author(s): Georgelin, R.L., Frkic, R.L., Jackson, C.J.
• Funding Organization(s): Australian Research Council (ARC)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.45 Å
• R-Value Free: 
  0.274 (Depositor), 0.274 (DCC) 
• R-Value Work: 
  0.224 (Depositor), 0.224 (DCC) 
• R-Value Observed: 
  0.227 (Depositor) 

Starting Model: in silico

Literature

Crystal structure of apo ecLacI transcription factor ancestor 1

Georgelin, R.L., Frkic, R.L., Jackson, C.J.

To be published.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

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

Biological Assembly Evidence: gel filtration

Biological Assembly 2  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 122.79 kDa 
• Atom Count: 8,184 
• Modeled Residue Count: 1,045 
• Deposited Residue Count: 1,120 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Ancestral LacI Transcription Factor	A [auth D], B [auth A], C, D [auth B]	280	Escherichia coli	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.45 Å
• R-Value Free:  0.274 (Depositor), 0.274 (DCC) 
• R-Value Work:  0.224 (Depositor), 0.224 (DCC) 
• R-Value Observed: 0.227 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 62.859	α = 90
b = 85.587	β = 90
c = 211.78	γ = 90

Software Package:

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

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-06-18 
Deposition Author(s): Georgelin, R.L., Frkic, R.L., Jackson, C.J.

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Funding Organization	Location	Grant Number
Australian Research Council (ARC)	Australia	CE200100012
Australian Research Council (ARC)	Australia	CE200100029

Revision History  

• Version 1.0: 2025-06-18
  Type: Initial release