4R1U

Crystal structure of Medicago truncatula cinnamoyl-CoA reductase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.18 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.202 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural Studies of Cinnamoyl-CoA Reductase and Cinnamyl-Alcohol Dehydrogenase, Key Enzymes of Monolignol Biosynthesis.

Pan, H.Zhou, R.Louie, G.V.Muhlemann, J.K.Bomati, E.K.Bowman, M.E.Dudareva, N.Dixon, R.A.Noel, J.P.Wang, X.

(2014) Plant Cell 26: 3709-3727

  • DOI: 10.1105/tpc.114.127399
  • Primary Citation of Related Structures:  
    4QTZ, 4QUK, 4R1S, 4R1T, 4R1U

  • PubMed Abstract: 
  • The enzymes cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the two key reduction reactions in the conversion of cinnamic acid derivatives into monolignol building blocks for lignin polymers in plant cell walls. Here, we describe detailed functional and structural analyses of CCRs from Medicago truncatula and Petunia hybrida and of an atypical CAD (CAD2) from M ...

    The enzymes cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the two key reduction reactions in the conversion of cinnamic acid derivatives into monolignol building blocks for lignin polymers in plant cell walls. Here, we describe detailed functional and structural analyses of CCRs from Medicago truncatula and Petunia hybrida and of an atypical CAD (CAD2) from M. truncatula. These enzymes are closely related members of the short-chain dehydrogenase/reductase (SDR) superfamily. Our structural studies support a reaction mechanism involving a canonical SDR catalytic triad in both CCR and CAD2 and an important role for an auxiliary cysteine unique to CCR. Site-directed mutants of CAD2 (Phe226Ala and Tyr136Phe) that enlarge the phenolic binding site result in a 4- to 10-fold increase in activity with sinapaldehyde, which in comparison to the smaller coumaraldehyde and coniferaldehyde substrates is disfavored by wild-type CAD2. This finding demonstrates the potential exploitation of rationally engineered forms of CCR and CAD2 for the targeted modification of monolignol composition in transgenic plants. Thermal denaturation measurements and structural comparisons of various liganded and unliganded forms of CCR and CAD2 highlight substantial conformational flexibility of these SDR enzymes, which plays an important role in the establishment of catalytically productive complexes of the enzymes with their NADPH and phenolic substrates.


    Organizational Affiliation

    Plant Biology Division, Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 xiaoqiang.wang@unt.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Cinnamoyl CoA reductaseA, B349Medicago truncatulaMutation(s): 0 
Gene Names: MtCCR2MTR_4g00694011424763MtrunA17_Chr4g0001321
EC: 1.2.1.44
UniProt
Find proteins for G7JEE5 (Medicago truncatula)
Explore G7JEE5 
Go to UniProtKB:  G7JEE5
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupG7JEE5
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download Ideal Coordinates CCD File 
C [auth A],
D [auth B],
E [auth B]
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.18 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.202 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 70.795α = 90
b = 96.821β = 90
c = 106.913γ = 90
Software Package:
Software NamePurpose
SCALEPACKdata scaling
SHARPphasing
PHENIXrefinement
PDB_EXTRACTdata extraction
HKL-2000data collection
DENZOdata reduction

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-10-01
    Type: Initial release
  • Version 1.1: 2014-11-12
    Changes: Database references
  • Version 1.2: 2017-11-22
    Changes: Refinement description