Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 43.98 kDa 
• Atom Count: 3630 
• Modelled Residue Count: 389 
• Deposited Residue Count: 389 
• Unique protein chains: 1

1CML

CHALCONE SYNTHASE FROM ALFALFA COMPLEXED WITH MALONYL-COA

• DOI: 10.2210/pdb1CML/pdb

• Classification: TRANSFERASE
• Organism(s): Medicago sativa
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 1999-03-30 Released: 1999-08-18 
• Deposition Author(s): Ferrer, J.-L., Jez, J., Bowman, M.E., Dixon, R., Noel, J.P.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.69 Å
• R-Value Free: 0.200 
• R-Value Work: 0.167 

Literature

Structure of chalcone synthase and the molecular basis of plant polyketide biosynthesis.

Ferrer, J.L., Jez, J.M., Bowman, M.E., Dixon, R.A., Noel, J.P.

(1999) Nat Struct Biol 6: 775-784

• PubMed: 10426957 
• DOI: 10.1038/11553
• Primary Citation of Related Structures:  
  1BI5, 1BQ6, 1CGK, 1CGZ, 1CHW, 1CML


• PubMed Abstract: 
  

Chalcone synthase (CHS) is pivotal for the biosynthesis of flavonoid antimicrobial phytoalexins and anthocyanin pigments in plants. It produces chalcone by condensing one p-coumaroyl- and three malonyl-coenzyme A thioesters into a polyketide reaction intermediate that cyclizes. The crystal structures of CHS alone and complexed with substrate and product analogs reveal the active site architecture that defines the sequence and chemistry of multiple decarboxylation and condensation reactions and provides a molecular understanding of the cyclization reaction leading to chalcone synthesis. The structure of CHS complexed with resveratrol also suggests how stilbene synthase, a related enzyme, uses the same substrates and an alternate cyclization pathway to form resveratrol. By using the three-dimensional structure and the large database of CHS-like sequences, we can identify proteins likely to possess novel substrate and product specificity. The structure elucidates the chemical basis of plant polyketide biosynthesis and provides a framework for engineering CHS-like enzymes to produce new products.

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Organizational Affiliation: 

Structural Biology Laboratory, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Rd., La Jolla, California 92037, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (CHALCONE SYNTHASE)	A	389	Medicago sativa	Mutation(s): 1  Gene Names: CHS2 EC: 2.3.1.74
UniProt
Find proteins for P30074 (Medicago sativa) Explore P30074  Go to UniProtKB:  P30074

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MLC (Subject of Investigation/LOI)	C [auth A]	MALONYL-COENZYME A C24 H38 N7 O19 P3 S LTYOQGRJFJAKNA-DVVLENMVSA-N
PIN (Subject of Investigation/LOI)	D [auth A]	PIPERAZINE-N,N'-BIS(2-ETHANESULFONIC ACID) C8 H18 N2 O6 S2 IHPYMWDTONKSCO-UHFFFAOYSA-N
SO4	B [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.69 Å
• R-Value Free: 0.200 
• R-Value Work: 0.167 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 97.768	α = 90
b = 97.768	β = 90
c = 65.228	γ = 120

Software Package:

Software Name	Purpose
CCP4	model building
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
CCP4	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1999-03-30 
• Released Date: 1999-08-18 
Deposition Author(s): Ferrer, J.-L., Jez, J., Bowman, M.E., Dixon, R., Noel, J.P.

Revision History  

• Version 1.0: 1999-08-18
  Type: Initial release
  
• Version 1.1: 2007-10-16
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2018-04-04
  Changes: Advisory, Data collection