B3TPQ6 (BCUSY_MAGGA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Beta-cubebene synthase Short name=Mg25 EC=4.2.3.128
Organism	Magnolia grandiflora (Southern magnolia)
Taxonomic identifier	3406 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Viridiplantae › Streptophyta › Streptophytina › Embryophyta › Tracheophyta › Euphyllophyta › Spermatophyta › Magnoliophyta › magnoliids › Magnoliales › Magnoliaceae › Magnolia

Protein attributes

Sequence length	550 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Sesquiterpene synthase converting farnesyl diphosphate into beta-cubebene (24.5%), alpha-muurolene (19.3%), delta-cadinol (18.6%), delta-elemene (16.0%), tau-muurolene (10.8%), and beta-elemene (10.8%). No activity with geranyl diphosphate or geranylgeranyl diphosphate. Ref.1
Catalytic activity	(2E,6E)-farnesyl diphosphate = beta-cubebene + diphosphate. Ref.1
Cofactor	Binds 3 magnesium ions per subunit Probable. Ref.1
Pathway	Secondary metabolite biosynthesis; terpenoid biosynthesis.
Tissue specificity	Expressed in young developing leaves and in stamens. Not detected in tepals and carpels. Ref.1
Domain	The Asp-Asp-Xaa-Xaa-Asp/Glu (DDXXD/E) motif is important for the catalytic activity, presumably through binding to Mg2+ By similarity.
Sequence similarities	Belongs to the terpene synthase family. Tpsa subfamily.
Biophysicochemical properties	Kinetic parameters: kcat is 0.35 x 10(-3) sec(-1) for farnesyl diphosphate. KM=1.07 µM for farnesyl diphosphate Ref.1 pH dependence: Optimum pH is 7.5. Temperature dependence: Optimum temperature is 24-26 degrees Celsius.

Ontologies

Keywords
Ligand	Magnesium Metal-binding
Molecular function	Lyase
Gene Ontology (GO)
Biological_process	farnesyl diphosphate metabolic process Inferred from direct assay Ref.1. Source: UniProtKB sesquiterpene biosynthetic process Inferred from direct assay Ref.1. Source: UniProtKB terpenoid biosynthetic process Inferred from electronic annotation. Source: UniProtKB-UniPathway
Molecular_function	magnesium ion binding Inferred from electronic annotation. Source: InterPro sesquiterpene synthase activity Inferred from direct assay Ref.1. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 550	550	Beta-cubebene synthase		PRO_0000419800
Regions
	Motif	303 – 307	5	DDXXD motif
Sites
	Metal binding	303	1	Magnesium or manganese 1 By similarity
	Metal binding	303	1	Magnesium or manganese 2 By similarity
	Metal binding	307	1	Magnesium or manganese 1 By similarity
	Metal binding	307	1	Magnesium or manganese 2 By similarity
	Metal binding	447	1	Magnesium or manganese 3 By similarity
	Metal binding	455	1	Magnesium or manganese 3 By similarity

Sequences

	Sequence		Length	Mass (Da)
	B3TPQ6 [UniParc]. Last modified September 2, 2008. Version 1. Checksum: BEC626551B7BECF6	FASTA	550	63,421
	10 20 30 40 50 60 MDSPTTQRPN MEIGRAFVNY HPSIWGEHFI AASPDVMRLD AHKGRGEELK EVVRNMFSTV 70 80 90 100 110 120 NDPLLKMNLI DAIQRLGVAY HFEMEIDKAL GQMYDDHING KDDGFDLQTL ALQFRLLRQQ 130 140 150 160 170 180 GYNVSSGVFA KFKDDEGNFS SILSKDTHGL LSLYEAAFLG THGDDILDEA ITFTTVHLKS 190 200 210 220 230 240 TLPHVSAPLT KLVELALEIP LHRRMERLQT RFYISIYEED RERNDVLLEF SKLEFLRLQS 250 260 270 280 290 300 LHQRELRDIS LWWKEMDLLA KLPFTRDRVL EGYFWTVGVY FEPHYSRARM IMTKMIAFAT 310 320 330 340 350 360 VMDDTYDVYG TLEELELLTA TIERWNRGDM DQLPDYMKVI FIALLDGVDA TEDDLTGEGK 370 380 390 400 410 420 SYRIYYLKEA VKDLAKAYLA EARWVSSGYV PTSEEYMKVA LISAVYPMLF VAFLIGMDEV 430 440 450 460 470 480 VTKEVLEWAI HMPTMLRTCS IVARLMDDIP SNKLEQERKH VSSSVECYMK EHGTSYHESI 490 500 510 520 530 540 QKLREMVASG WKDINKECLK PTPVPTAVIN VILNFTRVLE IIYQHRDGYT DASVETKEHI 550 ASLFVDPIPL

References

[1]

"Biochemical and genomic characterization of terpene synthases in Magnolia grandiflora." Lee S., Chappell J. Plant Physiol. 147:1017-1033(2008) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, COFACTOR, TISSUE SPECIFICITY.

Cross-references

Sequence databases
EMBL GenBank DDBJ	EU366429 Genomic DNA. Translation: ACC66281.1.
3D structure databases
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Enzyme and pathway databases
BioCyc	MetaCyc:MONOMER-14947.
UniPathway	UPA00213.
Family and domain databases
Gene3D	1.10.600.10. 1 hit. 1.50.30.10. 1 hit.
InterPro	IPR001906. Terpene_synth_N. IPR005630. Terpene_synthase_metal-bd. IPR008930. Terpenoid_cyclase/PrenylTrfase. IPR008949. Terpenoid_synth. [Graphical view]
Pfam	PF01397. Terpene_synth. 1 hit. PF03936. Terpene_synth_C. 1 hit. [Graphical view]
SUPFAM	SSF48239. Terp_cyc_toroid. 1 hit. SSF48576. Terpenoid_synth. 1 hit.
ProtoNet	Search...

Entry information

Entry name

BCUSY_MAGGA

Accession

Primary (citable) accession number: B3TPQ6

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 31, 2012
Last sequence update:	September 2, 2008
Last modified:	May 1, 2013
This is version 19 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program