Biological Assembly 1  

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 6-mer - A2B2C2 

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

Macromolecule Content

• Total Structure Weight: 273.87 kDa 
• Atom Count: 21,258 
• Modelled Residue Count: 2,481 
• Deposited Residue Count: 2,508 
• Unique protein chains: 3

 1RM6

Structure of 4-hydroxybenzoyl-CoA reductase from Thauera aromatica

• PDB DOI:  https://doi.org/10.2210/pdb1RM6/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Thauera aromatica
• Mutation(s): No 


• Deposited: 2003-11-27 Released: 2004-12-21 
• Deposition Author(s): Unciuleac, M., Warkentin, E., Page, C.C., Dutton, P.L., Boll, M., Ermler, U.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free: 0.173 
• R-Value Work: 0.152 
• R-Value Observed: 0.152 

Literature

Structure of a Xanthine Oxidase-Related 4-Hydroxybenzoyl-CoA Reductase with an Additional [4Fe-4S] Cluster and an Inverted Electron Flow

Unciuleac, M., Warkentin, E., Page, C.C., Boll, M., Ermler, U.

(2004) Structure 12: 2249-2256

• PubMed: 15576037 
• DOI: https://doi.org/10.1016/j.str.2004.10.008
• Primary Citation of Related Structures:  
  1RM6, 1SB3


• PubMed Abstract: 
  

The Mo-flavo-Fe/S-dependent heterohexameric protein complex 4-hydroxybenzoyl-CoA reductase (4-HBCR, dehydroxylating) is a central enzyme of the anaerobic degradation of phenolic compounds and belongs to the xanthine oxidase (XO) family of molybdenum enzymes. Its X-ray structure was established at 1.6 A resolution. The most pronounced difference between 4-HBCR and other structurally characterized members of the XO family is the insertion of 40 amino acids within the beta subunit, which carries an additional [4Fe-4S] cluster at a distance of 16.5 A to the isoalloxazine ring of FAD. The architecture of 4-HBCR and concomitantly performed electron transfer rate calculations suggest an inverted electron transfer chain from the donor ferredoxin via the [4Fe-4S] cluster to the Mo over a distance of 55 A. The binding site of 4-hydroxybenzoyl-CoA is located in an 18 A long channel lined up by several aromatic side chains around the aromatic moiety, which are proposed to shield and stabilize the postulated radical intermediates during catalysis.

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Organizational Affiliation: 

Institut für Biologie II, Mikrobiologie Schänzlestrasse 1, D-79104 Freiburg, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
4-hydroxybenzoyl-CoA reductase alpha subunit	A, D	769	Thauera aromatica	Mutation(s): 0  Gene Names: hcrA EC: 1.3.99.20 (PDB Primary Data), 1.1.7.1 (UniProt)
UniProt
Find proteins for O33819 (Thauera aromatica) Explore O33819  Go to UniProtKB:  O33819

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
4-hydroxybenzoyl-CoA reductase beta subunit	B, E	324	Thauera aromatica	Mutation(s): 0  Gene Names: hcrB EC: 1.3.99.20 (PDB Primary Data), 1.1.7.1 (UniProt)
UniProt
Find proteins for O33820 (Thauera aromatica) Explore O33820  Go to UniProtKB:  O33820

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
4-hydroxybenzoyl-CoA reductase gamma subunit	C, F	161	Thauera aromatica	Mutation(s): 0  Gene Names: hcrC EC: 1.3.99.20 (PDB Primary Data), 1.1.7.1 (UniProt)
UniProt
Find proteins for O33818 (Thauera aromatica) Explore O33818  Go to UniProtKB:  O33818

Small Molecules

Ligands 9 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PCD	I [auth A], U [auth D]	(MOLYBDOPTERIN-CYTOSINE DINUCLEOTIDE-S,S)-DIOXO-AQUA-MOLYBDENUM(V) C19 H26 Mo N8 O16 P2 S2 YEBYDVFRFUQMER-NBXMTLLYDD
FAD	M [auth B], W [auth E]	FLAVIN-ADENINE DINUCLEOTIDE C27 H33 N9 O15 P2 VWWQXMAJTJZDQX-UYBVJOGSSA-N
SF4	N [auth B], X [auth E]	IRON/SULFUR CLUSTER Fe4 S4 LJBDFODJNLIPKO-VKOJMFJBAC
EPE	J [auth A], K [auth A], L [auth A], V [auth D]	4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID C8 H18 N2 O4 S JKMHFZQWWAIEOD-UHFFFAOYSA-N
FES	O [auth C], P [auth C], Y [auth F], Z [auth F]	FE2/S2 (INORGANIC) CLUSTER Fe2 S2 NIXDOXVAJZFRNF-UHFFFAOYSA-N
SO4	T [auth D]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L
K	R [auth D]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N
CL	G [auth A], Q [auth D]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M
NA	H [auth A], S [auth D]	SODIUM ION Na FKNQFGJONOIPTF-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free: 0.173 
• R-Value Work: 0.152 
• R-Value Observed: 0.152 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 113.015	α = 90
b = 151.845	β = 90
c = 174.866	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
EPMR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2004-12-21 
Deposition Author(s): Unciuleac, M., Warkentin, E., Page, C.C., Dutton, P.L., Boll, M., Ermler, U.

Revision History  

• Version 1.0: 2004-12-21
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance