9ZZ0 | pdb_00009zz0

Crystal structure of MrtR bound to 3OH-C14 homoserine lactone

• PDB DOI: https://doi.org/10.2210/pdb9ZZ0/pdb

• Classification: TRANSCRIPTION
• Organism(s): Mesorhizobium tianshanense
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2026-01-06 Released: 2026-09-23 
• Deposition Author(s): Stoutland, I.M., Blackwell, H.E., Bingman, C.A.
• 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: 3.36 Å
• R-Value Free: 
  0.308 (Depositor), 0.312 (DCC) 
• R-Value Work: 
  0.253 (Depositor), 0.251 (DCC) 
• R-Value Observed: 
  0.256 (Depositor) 

Starting Model: in silico

Literature

MrtR of Mesorhizobium tianshanense reveals both activation and inhibition mechanisms of a LuxR-type quorum sensing receptor.

Stoutland, I.M., Blackwell, H.E.

(2026) Proc Natl Acad Sci U S A 

• DOI: https://doi.org/10.1073/pnas.2616692123

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 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: 82.87 kDa 
• Atom Count: 5,437 
• Modeled Residue Count: 712 
• Deposited Residue Count: 723 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
MrtR	A, B, C	241	Mesorhizobium tianshanense	Mutation(s): 0  Gene Names: mrtR
UniProt
Find proteins for Q45NF4 (Mesorhizobium tianshanense) Explore Q45NF4  Go to UniProtKB:  Q45NF4

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
A1C4G( Subject of Investigation/LOI)	D [auth A], E [auth B], G [auth C]	(3R)-3-hydroxy-N-[(3S)-2-oxooxolan-3-yl]tetradecanamide C18 H33 N O4 IKQUESGRCDRZTI-CVEARBPZSA-N
EDO	F [auth B]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.36 Å
• R-Value Free:  0.308 (Depositor), 0.312 (DCC) 
• R-Value Work:  0.253 (Depositor), 0.251 (DCC) 
• R-Value Observed: 0.256 (Depositor) 

Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 67.039	α = 90
b = 120.926	β = 98.81
c = 122.537	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
PDB_EXTRACT	data extraction
autoPROC	data reduction
autoPROC	data scaling
PHASER	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-09-23 
Deposition Author(s): Stoutland, I.M., Blackwell, H.E., Bingman, C.A.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	2R35GM131817-06

Revision History  

• Version 1.0: 2026-09-23
  Type: Initial release