Reviewed, UniProtKB/Swiss-Prot Q9SBQ9 (F3PH_PETHY)

Names and origin

Protein names

Recommended name:
    Flavonoid 3'-monooxygenase
    EC=1.14.13.21
Alternative name(s):
    Flavonoid 3'-hydroxylase
    Cytochrome P450 75B2

Gene names

Name:	CYP75B2
Synonyms:	HT1

Organism

Petunia hybrida (Petunia)

Taxonomic identifier

4102 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › lamiids › Solanales › Solanaceae › Petunioideae › Petunia

Protein attributes

Sequence length	512 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at transcript level.

General annotation (Comments)

Function	Catalyzes the 3'-hydroxylation of the flavonoid B-ring to the 3',4'-hydroxylated state. Convert naringenin to eriodictyol and dihydrokaempferol to dihydroquercetin.
Catalytic activity	A flavonoid + NADPH + O2 = a 3'-hydroxyflavonoid + NADP+ + H2O.
Cofactor	Heme group By similarity.
Pathway	Secondary metabolite biosynthesis; flavonoid biosynthesis.
Subcellular location	Endoplasmic reticulum membrane; Single-pass type III membrane protein Potential.
Tissue specificity	High expression in petals and ovaries and to a lower extent in sepals, pedicels, anthers and stems. Not detected in leaves, style or roots.
Developmental stage	High expression early in flower development and then declines as the corolla becomes fully pigmented and opened.
Miscellaneous	May act as a membrane anchor for localization of other, soluble, flavonoid enzymes to the endoplasmic reticulum.
Sequence similarities	Belongs to the cytochrome P450 family.

Ontologies

Keywords
Biological process	Flavonoid biosynthesis
Cellular component	Endoplasmic reticulum Membrane
Domain	Transmembrane
Ligand	Heme Iron Metal-binding NADP
Molecular function	Monooxygenase Oxidoreductase
Gene Ontology (GO)
Biological process	flavonoid biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	endoplasmic reticulum membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	electron carrier activity Inferred from electronic annotation. Source: InterPro flavonoid 3'-monooxygenase activity Inferred from electronic annotation. Source: EC heme binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 512	512	Flavonoid 3'-monooxygenase		PRO_0000052137
Regions
	Transmembrane	1 – 21	21	Potential
	Topological domain	22 – 512	491	Cytoplasmic Potential
Sites
	Metal binding	447	1	Iron (heme axial ligand) By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q9SBQ9-1 [UniParc]. Last modified May 1, 2000. Version 1. Checksum: 1843AC1BEB32BAE2	FASTA	512	56,936
	10 20 30 40 50 60 MEILSLILYT VIFSFLLQFI LRSFFRKRYP LPLPPGPKPW PIIGNLVHLG PKPHQSTAAM 70 80 90 100 110 120 AQTYGPLMYL KMGFVDVVVA ASASVAAQFL KTHDANFSSR PPNSGAEHMA YNYQDLVFAP 130 140 150 160 170 180 YGPRWRMLRK ICSVHLFSTK ALDDFRHVRQ DEVKTLTRAL ASAGQKPVKL GQLLNVCTTN 190 200 210 220 230 240 ALARVMLGKR VFADGSGDVD PQAAEFKSMV VEMMVVAGVF NIGDFIPQLN WLDIQGVAAK 250 260 270 280 290 300 MKKLHARFDA FLTDILEEHK GKIFGEMKDL LSTLISLKND DADNDGGKLT DTEIKALLLN 310 320 330 340 350 360 LFVAGTDTSS STVEWAIAEL IRNPKILAQA QQEIDKVVGR DRLVGELDLA QLTYLEAIVK 370 380 390 400 410 420 ETFRLHPSTP LSLPRIASES CEINGYFIPK GSTLLLNVWA IARDPNAWAD PLEFRPERFL 430 440 450 460 470 480 PGGEKPKVDV RGNDFEVIPF GAGRRICAGM NLGIRMVQLM IATLIHAFNW DLVSGQLPEM 490 500 510 LNMEEAYGLT LQRADPLVVH PRPRLEAQAY IG

References

[1]

"Isolation and characterization of a flavonoid 3'-hydroxylase cDNA clone corresponding to the Ht1 locus of Petunia hybrida." Brugliera F., Barri-Rewell G., Holton T.A., Mason J.G. Plant J. 19:441-451(1999) [PubMed: 10504566] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Old Glory Red. Tissue: Corolla.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AF155332 mRNA. Translation: AAD56282.1.
3D structure databases
ModBase	Search...
Enzyme and pathway databases
BRENDA	1.14.13.21. 2263.
Family and domain databases
InterPro	IPR001128. Cyt_P450. IPR017973. Cyt_P450_C. IPR017972. Cyt_P450_CS. IPR002401. Cyt_P450_E_grp-I. [Graphical view]
Gene3D	G3DSA:1.10.630.10. Cyt_P450. 1 hit.
PANTHER	PTHR19383. Cyt_P450. 1 hit.
Pfam	PF00067. p450. 1 hit. [Graphical view]
PRINTS	PR00463. EP450I. PR00385. P450.
PROSITE	PS00086. CYTOCHROME_P450. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

F3PH_PETHY

Accession

Primary (citable) accession number: Q9SBQ9

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 13, 2002
Last sequence update:	May 1, 2000
Last modified:	May 5, 2009
This is version 51 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)