Reviewed, UniProtKB/Swiss-Prot Q9FE01 (APX2_ORYSJ)

Names and origin

Protein names

Recommended name:
    L-ascorbate peroxidase 2, cytosolic
    EC=1.11.1.11
Alternative name(s):
    APXb
    OsAPx02

Gene names

Name:	APX2
Synonyms:	SS622
Ordered Locus Names:	Os07g0694700, LOC_Os07g49400
ORF Names:	P0627E10.14

Organism

Oryza sativa subsp. japonica (Rice)

Taxonomic identifier

39947 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › Liliopsida › Poales › Poaceae › BEP clade › Ehrhartoideae › Oryzeae › Oryza

Protein attributes

Sequence length	251 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Plays a key role in hydrogen peroxide removal. Ref.1
Catalytic activity	L-ascorbate + H2O2 = dehydroascorbate + 2 H2O.
Cofactor	Binds 1 heme B (iron-protoporphyrin IX) group By similarity. Binds 1 potassium or calcium ion per subunit By similarity.
Enzyme regulation	Inhibited by p-chloromercuriphenylsulfonic acid (CMPSA). Ref.1
Subcellular location	Cytoplasm Probable.
Tissue specificity	Expressed in aerial vegetative parts and reproductive organs. Ref.6
Induction	By stress and hormones. By infection with rice blast fungus (M.grisea). Circadian-regulation. Expression is higher during the light phase than during the dark phase. Ref.6
Sequence similarities	Belongs to the peroxidase family. Ascorbate peroxidase subfamily.
biophysicochemical properties	Kinetic parameters: KM=1 mM for ascorbate KM=0.7 mM for H2O2 Vmax=20 mM/min/mg enzyme with ascorbate as substrate Vmax=3 mM/min/mg enzyme with H2O2 as substrate pH dependence: Optimum pH is 6-7.

Ontologies

Keywords
Biological process	Hydrogen peroxide Stress response
Cellular component	Cytoplasm
Ligand	Calcium Heme Iron Metal-binding Potassium
Molecular function	Oxidoreductase Peroxidase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	hydrogen peroxide catabolic 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-SubCell
Molecular function	L-ascorbate peroxidase activity Inferred from electronic annotation. Source: EC calcium ion binding Inferred from electronic annotation. Source: UniProtKB-KW heme binding Inferred from electronic annotation. Source: InterPro potassium ion binding 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 – 251	251	L-ascorbate peroxidase 2, cytosolic		PRO_0000055594
Sites
	Active site	43	1	Proton acceptor By similarity
	Metal binding	164	1	Iron (heme axial ligand) By similarity
	Metal binding	165	1	Potassium or calcium By similarity
	Metal binding	181	1	Potassium or calcium By similarity
	Metal binding	183	1	Potassium or calcium By similarity
	Metal binding	186	1	Potassium or calcium; via carbonyl oxygen By similarity
	Metal binding	188	1	Potassium or calcium By similarity
	Site	39	1	Transition state stabilizer By similarity
Experimental info
	Sequence conflict	202 – 215	14	GLLQL…ALMAD → PSSSCQVTKPSWLT Ref.5

Sequences

	Sequence		Length	Mass (Da)
	Q9FE01-1 [UniParc]. Last modified March 1, 2001. Version 1. Checksum: D6497B224285DF93	FASTA	251	27,118
	10 20 30 40 50 60 MGSKSYPTVS DEYLAAVGKA KRKLRGLIAE KNCAPLMLRL AWHSAGTFDV SSRTGGPFGT 70 80 90 100 110 120 MKNPGEQSHA ANAGLDIAVR LLDPIKDQLP ILSYADFYQL AGVVAVEVTG GPEVPFHPGR 130 140 150 160 170 180 QDKPEPPPEG RLPDATQGSD HLRQVFSAQM GLSDKDIVAL SGGHTLGRCH KERSGFEGAW 190 200 210 220 230 240 TSNPLIFDNS YFTELVSGEK EGLLQLPSDK ALMADPAFRP LVEKYAADED AFFADYAEAH 250 LKLSELGFAE E

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Purification and characterization of two ascorbate peroxidases of rice (Oryza sativa L.) expressed in Escherichia coli." Lu Z., Takano T., Liu S. Biotechnol. Lett. 27:63-67(2005) [PubMed: 15685422] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], ENZYME REGULATION, FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES. Strain: cv. Nipponbare.
[2]	"The expression of two cytosolic ascorbate peroxidase genes in rice." Morita S., Kaminaka H., Masumura T., Tanaka K. Submitted (NOV-2000) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Nipponbare.
[3]	"Oryza sativa nipponbare chromosome 7 genomic DNA sequence." The international rice genome sequencing project (IRGSP) consortium Submitted (MAY-2002) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: cv. Nipponbare.
[4]	"Rice proteome database based on two-dimensional polyacrylamide gel electrophoresis: its status in 2003." Komatsu S., Kojima K., Suzuki K., Ozaki K., Higo K. Nucleic Acids Res. 32:D388-D392(2004) [PubMed: 14681440] [Abstract] Cited for: PROTEIN SEQUENCE OF 26-35. Strain: cv. Nipponbare. Tissue: Anther, Panicle and Stem.
[5]	Uchimiya H. Submitted (NOV-1993) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 202-251. Tissue: Callus.
[6]	"Importance of ascorbate peroxidases OsAPX1 and OsAPX2 in the rice pathogen response pathways and growth and reproduction revealed by their transcriptional profiling." Agrawal G.K., Jwa N.-S., Iwahashi H., Rakwal R. Gene 322:93-103(2003) [PubMed: 14644501] [Abstract] Cited for: TISSUE SPECIFICITY, INDUCTION.
[7]	"Analysis of the molecular evolutionary history of the ascorbate peroxidase gene family: inferences from the rice genome." Teixeira F.K., Menezes-Benavente L., Margis R., Margis-Pinheiro M. J. Mol. Evol. 59:761-770(2004) [PubMed: 15599508] [Abstract] Cited for: NOMENCLATURE.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AB053297 mRNA. Translation: BAB20889.1. AB050724 mRNA. Translation: BAB17666.1. AP005199 Genomic DNA. Translation: BAC84063.1. D25238 mRNA. Translation: BAA04962.1.
PIR	T04114.
RefSeq	NP_001060741.1.
UniGene	Os.12693
3D structure databases
HSSP	HSSP built from PDB template 1OAF based on UniProtKB Q43758.
SMR	Q9FE01. Positions 4-250.
ModBase	Search...
Protein family/group databases
PeroxiBase	1866. OsAPx02.
2-D gel databases
ANU-2DPAGE	Q9FE01.
Genome annotation databases
GeneID	4344397.
KEGG	osa:4344397.
Organism-specific databases
Gramene	Q9FE01.
Family and domain databases
InterPro	IPR002207. Asc_perxdse. IPR002016. Haem_peroxidase_pln/fun/bac. IPR019794. Peroxidases_AS. IPR019793. Peroxidases_heam-ligand_BS. [Graphical view]
Pfam	PF00141. peroxidase. 1 hit. [Graphical view]
PRINTS	PR00459. ASPEROXIDASE. PR00458. PEROXIDASE.
PROSITE	PS00435. PEROXIDASE_1. 1 hit. PS00436. PEROXIDASE_2. 1 hit. PS50873. PEROXIDASE_4. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

APX2_ORYSJ

Accession

Primary (citable) accession number: Q9FE01
Secondary accession number(s): Q40735

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 25, 2005
Last sequence update:	March 1, 2001
Last modified:	June 16, 2009
This is version 46 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)