Reviewed, UniProtKB/Swiss-Prot Q42593 (APXT_ARATH)

Names and origin

Protein names

Recommended name:
    L-ascorbate peroxidase T, chloroplastic
    EC=1.11.1.11
Alternative name(s):
    Thylakoid-bound ascorbate peroxidase
      Short name=tAPX
      Short name=AtAPx06

Gene names

Name:	APXT
Ordered Locus Names:	At1g77490
ORF Names:	T5M16.8

Organism

Arabidopsis thaliana (Mouse-ear cress) [Complete proteome]

Taxonomic identifier

3702 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › rosids › eurosids II › Brassicales › Brassicaceae › Arabidopsis

Protein attributes

Sequence length	426 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level.

General annotation (Comments)

Function	Plays a key role in hydrogen peroxide removal By similarity.
Catalytic activity	L-ascorbate + H2O2 = dehydroascorbate + 2 H2O.
Cofactor	Binds 1 heme B (iron-protoporphyrin IX) group per subunit. Binds 1 potassium or calcium ion per subunit By similarity.
Subcellular location	Plastid › chloroplast thylakoid membrane; Single-pass membrane protein Potential.
Developmental stage	Down-regulated during leaf senescence. Ref.5
Sequence similarities	Belongs to the peroxidase family. Ascorbate peroxidase subfamily.

Ontologies

Keywords
Biological process	Hydrogen peroxide
Cellular component	Chloroplast Membrane Plastid Thylakoid
Domain	Transit peptide Transmembrane
Ligand	Calcium Heme Iron Metal-binding Potassium
Molecular function	Oxidoreductase Peroxidase
Technical term	Complete proteome
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	chloroplast thylakoid membrane Inferred from direct assay. Source: TAIR integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
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
	Transit peptide	1 – ?		Chloroplast Potential
	Transit peptide	? – 78		Thylakoid Potential
	Chain	79 – 426	348	L-ascorbate peroxidase T, chloroplastic		PRO_0000261327
Regions
	Transmembrane	397 – 417	21	Potential
Sites
	Active site	112	1	Proton acceptor By similarity
	Metal binding	241	1	Iron (heme axial ligand) By similarity
	Metal binding	242	1	Potassium or calcium By similarity
	Metal binding	274	1	Potassium or calcium By similarity
	Metal binding	281	1	Potassium or calcium By similarity
	Site	108	1	Transition state stabilizer By similarity
Experimental info
	Sequence conflict	73	1	M → K in CAA67426. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	Q42593-1 [UniParc]. Last modified November 28, 2006. Version 2. Checksum: 9205E8E77B73BBAC	FASTA	426	46,092
	10 20 30 40 50 60 MSVSLSAASH LLCSSTRVSL SPAVTSSSSS PVVALSSSTS PHSLGSVASS SLFPHSSFVL 70 80 90 100 110 120 QKKHPINGTS TRMISPKCAA SDAAQLISAK EDIKVLLRTK FCHPILVRLG WHDAGTYNKN 130 140 150 160 170 180 IEEWPLRGGA NGSLRFEAEL KHAANAGLLN ALKLIQPLKD KYPNISYADL FQLASATAIE 190 200 210 220 230 240 EAGGPDIPMK YGRVDVVAPE QCPEEGRLPD AGPPSPADHL RDVFYRMGLD DKEIVALSGA 250 260 270 280 290 300 HTLGRARPDR SGWGKPETKY TKTGPGEAGG QSWTVKWLKF DNSYFKDIKE KRDDDLLVLP 310 320 330 340 350 360 TDAALFEDPS FKNYAEKYAE DVAAFFKDYA EAHAKLSNLG AKFDPPEGIV IENVPEKFVA 370 380 390 400 410 420 AKYSTGKKEL SDSMKKKIRA EYEAIGGSPD KPLPTNYFLN IIIAIGVLVL LSTLFGGNNN SDFSGF

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"From sequence analysis of three novel ascorbate peroxidases from Arabidopsis thaliana to structure, function and evolution of seven types of ascorbate peroxidase." Jespersen H.M., Kjaersgaard I.V.H., Oestergaard L., Welinder K.G. Biochem. J. 326:305-310(1997) [PubMed: 9291097] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Columbia.
[2]	"Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana." Theologis A., Ecker J.R., Palm C.J., Federspiel N.A., Kaul S., White O., Alonso J., Altafi H., Araujo R., Bowman C.L., Brooks S.Y., Buehler E., Chan A., Chao Q., Chen H., Cheuk R.F., Chin C.W., Chung M.K. , Conn L., Conway A.B., Conway A.R., Creasy T.H., Dewar K., Dunn P., Etgu P., Feldblyum T.V., Feng J.-D., Fong B., Fujii C.Y., Gill J.E., Goldsmith A.D., Haas B., Hansen N.F., Hughes B., Huizar L., Hunter J.L., Jenkins J., Johnson-Hopson C., Khan S., Khaykin E., Kim C.J., Koo H.L., Kremenetskaia I., Kurtz D.B., Kwan A., Lam B., Langin-Hooper S., Lee A., Lee J.M., Lenz C.A., Li J.H., Li Y.-P., Lin X., Liu S.X., Liu Z.A., Luros J.S., Maiti R., Marziali A., Militscher J., Miranda M., Nguyen M., Nierman W.C., Osborne B.I., Pai G., Peterson J., Pham P.K., Rizzo M., Rooney T., Rowley D., Sakano H., Salzberg S.L., Schwartz J.R., Shinn P., Southwick A.M., Sun H., Tallon L.J., Tambunga G., Toriumi M.J., Town C.D., Utterback T., Van Aken S., Vaysberg M., Vysotskaia V.S., Walker M., Wu D., Yu G., Fraser C.M., Venter J.C., Davis R.W. Nature 408:816-820(2000) [PubMed: 11130712] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: cv. Columbia.
[3]	"Large-scale analysis of RIKEN Arabidopsis full-length (RAFL) cDNAs." Totoki Y., Seki M., Ishida J., Nakajima M., Enju A., Kamiya A., Narusaka M., Shin-i T., Nakagawa M., Sakamoto N., Oishi K., Kohara Y., Kobayashi M., Toyoda A., Sakaki Y., Sakurai T., Iida K., Akiyama K. , Satou M., Toyoda T., Konagaya A., Carninci P., Kawai J., Hayashizaki Y., Shinozaki K. Submitted (JUL-2006) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: cv. Columbia.
[4]	"Full-length cDNA from Arabidopsis thaliana." Brover V.V., Troukhan M.E., Alexandrov N.A., Lu Y.-P., Flavell R.B., Feldmann K.A. Submitted (MAR-2002) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
[5]	"Expression of the Apx gene family during leaf senescence of Arabidopsis thaliana." Panchuk I.I., Zentgraf U., Volkov R.A. Planta 222:926-932(2005) [PubMed: 16034597] [Abstract] Cited for: DEVELOPMENTAL STAGE.

Cross-references

Sequence databases
EMBLGenBankDDBJ	X98926 mRNA. Translation: CAA67426.1. AC010704 Genomic DNA. Translation: AAG51660.1. AK229693 mRNA. Translation: BAF01533.1. AY085554 mRNA. Translation: AAM62777.1.
IPI	IPI00542810.
PIR	C96804.
RefSeq	NP_177873.1.
UniGene	At.25463
3D structure databases
HSSP	HSSP built from PDB template 1IYN based on UniProtKB Q8LNY5.
SMR	Q42593. Positions 79-352.
ModBase	Search...
Proteomic databases
PRIDE	Q42593.
Genome annotation databases
GeneID	844085.
GenomeReviews	Gene locus AT1G77490 in contig CT485782_GR.
KEGG	ath:AT1G77490.
NMPDR	fig|3702.1.peg.7290.
Organism-specific databases
GeneFarm	1953. 146.
TAIR	At1g77490.
Enzyme and pathway databases
BRENDA	1.11.1.11. 302.
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. False negative. PS50873. PEROXIDASE_4. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

APXT_ARATH

Accession

Primary (citable) accession number: Q42593
Secondary accession number(s): Q9CAQ6

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 28, 2006
Last sequence update:	November 28, 2006
Last modified:	June 16, 2009
This is version 56 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)