PDBsum entry: 1cml

Transferase

PDB id: 1cml

Contents

Protein chain

389 a.a. *

Ligands

SO4

MLC-PIN

Waters ×399

* Residue conservation analysis

PDB id:

1cml

Name:

Transferase

Title:

Chalcone synthase from alfalfa complexed with malonyl-coa

Structure:

Protein (chalcone synthase). Chain: a. Synonym: chs. Engineered: yes. Mutation: yes

Source:

Medicago sativa. Organism_taxid: 3879. Tissue: 21 day old root nodule. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.

Biol. unit:

Dimer (from PDB file)

Resolution:

1.69Å R-factor: 0.167 R-free: 0.200

Authors:

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

Key ref:

J.L.Ferrer et al. (1999). Structure of chalcone synthase and the molecular basis of plant polyketide biosynthesis. Nat Struct Biol, 6, 775-784. PubMed id: 10426957 DOI: 10.1038/11553

Date:

30-Mar-99 Release date: 18-Aug-99

Protein chain

P30074  (CHS2_MEDSA) -  Chalcone synthase 2

Seq: 389 a.a.

Struc: 389 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.2.3.1.74 - Naringenin-chalcone synthase.
• Pathway: Chalcone and Stilbene Biosynthesis
• Reaction: 3 malonyl-CoA + 4-coumaroyl-CoA = 4 CoA + naringenin chalcone + 3 CO₂

3 × malonyl-CoA (Bound ligand (Het Group name = MLC) corresponds exactly) + 4-coumaroyl-CoA = 4 × CoA + naringenin chalcone + 3 × CO(2)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Biological process: metabolic process (4 terms)
• Biochemical function: catalytic activity (5 terms)

reference

DOI no: 10.1038/11553

Nat Struct Biol 6:775-784 (1999)

PubMed id: 10426957

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

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

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.

Selected figure(s)

Figure 1.
Figure 1. Products, product analogs and inhibitors. a, Chemical structures of chalcone, naringenin, resveratrol and cerulenin. b, Stereoview of the final SIGMAA-weighted 2F[o] - F[c] electron density map of the CHS−resveratrol complex in the vicinity of the resveratrol binding site. The map is contoured at 1 .

Figure 2.
Figure 2. a, Ribbon representation of the CHS homodimer. Monomer A is gold, monomer B is blue, and naringenin is shown as a CPK molecule. The approximate C positions of Met 137 are shown as yellow ellipses and labeled accordingly. Naringenin completely fills the coumaroyl-binding and cyclization pockets, while the CoA binding tunnels are highlighted by black arrows. Produced with MOLSCRIPT^46 and rendered with POV-Ray^47. b, Stereoview of the gold monomer's C backbone. The orientation of the gold monomer is exactly the same as in (a). Every 20 residues are numbered, starting with residue 3 and including the C-terminal residue, 389.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nat Struct Biol (1999, 6, 775-784) copyright 1999.

Figures were selected by an automated process.