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P30074 (CHS2_MEDSA) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 82. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (3) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Chalcone synthase 2

EC=2.3.1.74
Alternative name(s):
Naringenin-chalcone synthase 2
Gene names
Name:CHS2
OrganismMedicago sativa (Alfalfa)
Taxonomic identifier3879 [NCBI]
Taxonomic lineageEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsfabidsFabalesFabaceaePapilionoideaeTrifolieaeMedicago

Protein attributes

Sequence length389 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

The primary product of this enzyme is 4,2',4',6'-tetrahydroxychalcone (also termed naringenin-chalcone or chalcone) which can under specific conditions spontaneously isomerize into naringenin. Ref.3 Ref.4 Ref.5 Ref.6

Catalytic activity

3 malonyl-CoA + 4-coumaroyl-CoA = 4 CoA + naringenin chalcone + 3 CO2.

Pathway

Secondary metabolite biosynthesis; flavonoid biosynthesis.

Subunit structure

Homodimer Probable.

Sequence similarities

Belongs to the chalcone/stilbene synthases family.

Biophysicochemical properties

Kinetic parameters:

KM=4.1 µM for malonyl-CoA Ref.3 Ref.4 Ref.5

KM=4.5 µM for 4-coumaroyl-CoA

KM=2.2 µM for benzoyl-CoA

KM=4.1 µM for hexanoyl-CoA

KM=5.1 µM for phenylacetyl-CoA

KM=5.2 µM for feruloyl-CoA

Ontologies

Keywords
   Biological processFlavonoid biosynthesis
   Molecular functionAcyltransferase
Transferase
   Technical term3D-structure
Gene Ontology (GO)
   Biological_processchalcone biosynthetic process

Inferred from direct assay Ref.3. Source: UniProtKB

flavonoid biosynthetic process

Inferred from electronic annotation. Source: UniProtKB-UniPathway

   Molecular_functionnaringenin-chalcone synthase activity

Inferred from direct assay Ref.3. Source: UniProtKB

Complete GO annotation...

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 389389Chalcone synthase 2
PRO_0000216007

Regions

Region55 – 628Coenzyme A binding
Region216 – 2172Substrate binding

Sites

Active site1641Acyl-thioester intermediate Probable
Binding site1971Substrate
Binding site3081Coenzyme A; via amide nitrogen

Experimental info

Mutagenesis1641C → A, D or S: Loss of activity. Ref.3
Mutagenesis2151F → S, W or Y: Drastically reduces catalytic efficiency. Ref.3 Ref.5
Mutagenesis2561G → A: Decreases catalytic efficiency 2-fold. Ref.4
Mutagenesis2561G → F or L: Drastically reduces catalytic efficiency. Ref.4
Mutagenesis2561G → V: Decreases catalytic efficiency 7-fold. Ref.4
Mutagenesis2651F → V: Decreases catalytic efficiency 2-fold. Ref.5
Mutagenesis3031H → A, D, N or T: Drastically reduces catalytic efficiency. Ref.3
Mutagenesis3031H → Q: Decreases catalytic efficiency 13-fold. Ref.3
Mutagenesis3361N → A, D, H, K or Q: Drastically reduces catalytic efficiency. Ref.3

Secondary structure

................................................................... 389
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P30074 [UniParc].

Last modified April 1, 1993. Version 1.
Checksum: E03422EE332A5408

FASTA38942,706
        10         20         30         40         50         60 
MVSVSEIRKA QRAEGPATIL AIGTANPANC VEQSTYPDFY FKITNSEHKT ELKEKFQRMC 

        70         80         90        100        110        120 
DKSMIKRRYM YLTEEILKEN PNVCEYMAPS LDARQDMVVV EVPRLGKEAA VKAIKEWGQP 

       130        140        150        160        170        180 
KSKITHLIVC TTSGVDMPGA DYQLTKLLGL RPYVKRYMMY QQGCFAGGTV LRLAKDLAEN 

       190        200        210        220        230        240 
NKGARVLVVC SEVTAVTFRG PSDTHLDSLV GQALFGDGAA ALIVGSDPVP EIEKPIFEMV 

       250        260        270        280        290        300 
WTAQTIAPDS EGAIDGHLRE AGLTFHLLKD VPGIVSKNIT KALVEAFEPL GISDYNSIFW 

       310        320        330        340        350        360 
IAHPGGPAIL DQVEQKLALK PEKMNATREV LSEYGNMSSA CVLFILDEMR KKSTQNGLKT 

       370        380 
TGEGLEWGVL FGFGPGLTIE TVVLRSVAI 

« Hide

References

[1]"Stress responses in alfalfa (Medicago sativa L.). 15. Characterization and expression patterns of members of a subset of the chalcone synthase multigene family."
Junghans H., Dalkin K., Dixon R.A.
Plant Mol. Biol. 22:239-253(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[2]"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.
Nat. Struct. Biol. 6:775-784(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.56 ANGSTROMS) IN COMPLEX WITH SUBSTRATE AND COENZYME A.
[3]"Dissection of malonyl-coenzyme A decarboxylation from polyketide formation in the reaction mechanism of a plant polyketide synthase."
Jez J.M., Ferrer J.L., Bowman M.E., Dixon R.A., Noel J.P.
Biochemistry 39:890-902(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.69 ANGSTROMS) IN COMPLEX WITH COENZYME A, FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, MUTAGENESIS OF CYS-164; PHE-215; HIS-303 AND ASN-336.
[4]"Structure-guided programming of polyketide chain-length determination in chalcone synthase."
Jez J.M., Bowman M.E., Noel J.P.
Biochemistry 40:14829-14838(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.45 ANGSTROMS), FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, MUTAGENESIS OF GLY-256.
[5]"Expanding the biosynthetic repertoire of plant type III polyketide synthases by altering starter molecule specificity."
Jez J.M., Bowman M.E., Noel J.P.
Proc. Natl. Acad. Sci. U.S.A. 99:5319-5324(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.63 ANGSTROMS), FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, MUTAGENESIS OF PHE-215 AND PHE-265.
[6]"An aldol switch discovered in stilbene synthases mediates cyclization specificity of type III polyketide synthases."
Austin M.B., Bowman M.E., Ferrer J.-L., Schroeder J., Noel J.P.
Chem. Biol. 11:1179-1194(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.90 ANGSTROMS), FUNCTION.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
L02902 mRNA. Translation: AAA02824.1.
PIRS35164.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1BI5X-ray1.56A1-389[»]
1BQ6X-ray1.56A2-389[»]
1CGKX-ray1.84A1-389[»]
1CGZX-ray1.70A1-389[»]
1CHWX-ray1.90A/B1-389[»]
1CMLX-ray1.69A1-389[»]
1D6FX-ray1.69A1-389[»]
1D6HX-ray2.15A3-389[»]
1D6IX-ray2.00A/B2-389[»]
1I86X-ray1.50A1-389[»]
1I88X-ray1.45A/B1-389[»]
1I89X-ray1.86A/B1-389[»]
1I8BX-ray1.95A/B1-389[»]
1JWXX-ray1.63A1-389[»]
1U0VX-ray1.90A/B1-389[»]
1U0WX-ray2.00A/B/C/D1-389[»]
ProteinModelPortalP30074.
SMRP30074. Positions 3-389.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Enzyme and pathway databases

UniPathwayUPA00154.

Family and domain databases

Gene3D3.40.47.10. 2 hits.
InterProIPR012328. Chalcone/stilbene_synth_C.
IPR018088. Chalcone/stilbene_synthase_AS.
IPR001099. Chalcone/stilbene_synthase_N.
IPR011141. Polyketide_synthase_type-III.
IPR016039. Thiolase-like.
IPR016038. Thiolase-like_subgr.
[Graphical view]
PfamPF02797. Chal_sti_synt_C. 1 hit.
PF00195. Chal_sti_synt_N. 1 hit.
[Graphical view]
PIRSFPIRSF000451. PKS_III. 1 hit.
SUPFAMSSF53901. SSF53901. 2 hits.
PROSITEPS00441. CHALCONE_SYNTH. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceP30074.

Entry information

Entry nameCHS2_MEDSA
AccessionPrimary (citable) accession number: P30074
Entry history
Integrated into UniProtKB/Swiss-Prot: April 1, 1993
Last sequence update: April 1, 1993
Last modified: February 19, 2014
This is version 82 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

PATHWAY comments

Index of metabolic and biosynthesis pathways