Reviewed, UniProtKB/Swiss-Prot Q9ZWQ9 (FLS_CITUN)

Names and origin

Protein names

Recommended name:
    Flavonol synthase/flavanone 3-hydroxylase
    EC=1.14.11.23
    EC=1.14.11.9
Alternative name(s):
    CitFLS
      Short name=FLS

Gene names

Name:

FLS

Organism

Citrus unshiu (Satsuma orange)

Taxonomic identifier

55188 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › rosids › eurosids II › Sapindales › Rutaceae › Citrus

Protein attributes

Sequence length	335 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Catalyzes the formation of flavonols from dihydroflavonols. It can act on dihydrokaempferol to produce kaempferol, on dihydroquercetin to produce quercitin and on dihydromyricetin to produce myricetin By similarity.
Catalytic activity	A dihydroflavonol + 2-oxoglutarate + O(2) = a flavonol + succinate + CO(2) + H(2)O. A flavanone + 2-oxoglutarate + O(2) = a dihydroflavonol + succinate + CO(2).
Cofactor	Binds 1 iron ion per subunit By similarity. Binds 1 ascorbate molecule per subunit By similarity.
Pathway	Secondary metabolite biosynthesis; flavonoid biosynthesis.
Subcellular location	CytoplasmBy similarity.
Tissue specificity	In the juice sacs/segment epidermis (edible part) at the early developmental stage.
Developmental stage	Increases in the peel during fruit maturation.
Sequence similarities	Belongs to the iron/ascorbate-dependent oxidoreductase family.

Ontologies

Keywords
Biological process	Flavonoid biosynthesis
Cellular component	Cytoplasm
Ligand	Iron Metal-binding Vitamin C
Molecular function	Dioxygenase Oxidoreductase
Technical term	Direct protein sequencing
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	cytoplasm Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	L-ascorbic acid binding Inferred from electronic annotation. Source: UniProtKB-KW flavonol synthase activity Inferred from electronic annotation. Source: EC iron ion binding Inferred from electronic annotation. Source: UniProtKB-KW naringenin 3-dioxygenase activity Inferred from electronic annotation. Source: EC oxidoreductase activity, acting on single donors with incorporation of molecular oxygen, incorporation of two atoms of oxygen Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 335	335	Flavonol synthase/flavanone 3-hydroxylase		PRO_0000067292
Sites
	Metal binding	221	1	Iron By similarity
	Metal binding	223	1	Iron By similarity
	Metal binding	277	1	Iron By similarity
Experimental info
	Mutagenesis	68	1	G → A: Reduces activity 95%
	Mutagenesis	68	1	G → P: Results in complete loss of activity
	Mutagenesis	207	1	P → G: No effect
	Mutagenesis	261	1	G → A: Reduces activity 95%
	Mutagenesis	261	1	G → P: Results in complete loss of activity

Sequences

	Sequence		Length	Mass (Da)
	Q9ZWQ9-1 [UniParc]. Last modified May 1, 1999. Version 1. Checksum: 157E1AFA4C47564B	FASTA	335	37,899
	10 20 30 40 50 60 MEVERVQAIA SLSHSNGTIP AEFIRPEKEQ PASTTYHGPA PEIPTIDLDD PVQDRLVRSI 70 80 90 100 110 120 AEASREWGIF QVTNHGIPSD LICKLQAVGK EFFELPQEEK EVYSRPADAK DVQGYGTKLQ 130 140 150 160 170 180 KEVEGKKSWV DHLFHRVWPP SSINYRFWPK NPPSYRAVNE EYAKYMREVV DKLFTYLSLG 190 200 210 220 230 240 LGVEGGVLKE AAGGDDIEYM LKINYYPPCP RPDLALGVVA HTDLSALTVL VPNEVPGLQV 250 260 270 280 290 300 FKDDRWIDAK YIPNALVIHI GDQIEILSNG KYKAVLHRTT VNKDKTRMSW PVFLEPPADT 310 320 330 VVGPLPQLVD DENPPKYKAK KFKDYSYCKL NKLPQ

References

[1]	"Flavonol synthase gene expression during citrus fruit development." Moriguchi T., Kita M., Ogawa K., Tomono Y., Endo T., Omura M. Physiol. Plantarum 114:251-258(2002) [PubMed: 11903972] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Satsuma Mandarin.
[2]	"Functional expression and mutational analysis of flavonol synthase from Citrus unshiu." Wellmann F., Lukacin R., Moriguchi T., Britsch L., Schiltz E., Matern U. Eur. J. Biochem. 269:4134-4142(2002) [PubMed: 12180990] [Abstract] Cited for: PROTEIN SEQUENCE OF 1-14, CHARACTERIZATION, MUTAGENESIS OF GLY-68 AND GLY-261.
[3]	"Flavonol synthase from Citrus unshiu is a bifunctional dioxygenase." Lukacin R., Wellmann F., Britsch L., Martens S., Matern U. Phytochemistry 62:287-292(2003) [PubMed: 12620339] [Abstract] Cited for: FUNCTION.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AB011796 mRNA. Translation: BAA36554.1.
3D structure databases
HSSP	HSSP built from PDB template 1GP6 based on UniProtKB Q96323.
ModBase	Search...
Family and domain databases
InterPro	IPR005123. 2OG-FeII_Oase. [Graphical view]
Pfam	PF03171. 2OG-FeII_Oxy. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

FLS_CITUN

Accession

Primary (citable) accession number: Q9ZWQ9

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 11, 2001
Last sequence update:	May 1, 1999
Last modified:	November 4, 2008
This is version 45 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)