Reviewed, UniProtKB/Swiss-Prot P48534 (APX1_PEA)

Names and origin

Protein names

Recommended name:
    L-ascorbate peroxidase, cytosolic
      Short name=AP
    EC=1.11.1.11
Alternative name(s):
    PsAPx01

Gene names

Name:	APX1
Synonyms:	APPX1

Organism

Pisum sativum (Garden pea)

Taxonomic identifier

3888 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › rosids › eurosids I › Fabales › Fabaceae › Papilionoideae › Fabeae › Pisum

Protein attributes

Sequence length	250 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Plays a key role in hydrogen peroxide removal.
Catalytic activity	L-ascorbate + H(2)O(2) = dehydroascorbate + 2 H(2)O.
Cofactor	Binds 1 heme B (iron-protoporphyrin IX) group per subunit. Binds 1 potassium or calcium ion per subunit.
Subcellular location	Cytoplasm.
Induction	By stress.
Sequence similarities	Belongs to the peroxidase family. Ascorbate peroxidase subfamily.

Ontologies

Keywords
Biological process	Hydrogen peroxide Stress response
Cellular component	Cytoplasm
Ligand	Calcium Heme Iron Metal-binding Potassium
Molecular function	Oxidoreductase Peroxidase
Technical term	3D-structure
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-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 iron ion binding Inferred from electronic annotation. Source: UniProtKB-KW 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

Initiator methionine

1

1

Removed

Chain

2 – 250

249

L-ascorbate peroxidase, cytosolic

PRO_0000055597

Sites

Active site

42

1

Proton acceptor

Metal binding

163

1

Iron (heme axial ligand)

Metal binding

164

1

Potassium or calcium

Metal binding

180

1

Potassium or calcium

Metal binding

182

1

Potassium or calcium

Metal binding

185

1

Potassium or calcium; via carbonyl oxygen

Metal binding

187

1

Potassium or calcium

Site

38

1

Transition state stabilizer

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

250

Helix Strand Turn

Details...

Helix

10 – 30

21

Helix

33 – 44

12

Turn

49 – 52

4

Beta strand

55 – 58

4

Helix

59 – 61

3

Helix

63 – 66

4

Helix

69 – 71

3

Helix

74 – 86

13

Helix

93 – 107

15

Helix

138 – 145

8

Turn

146 – 148

3

Helix

153 – 160

8

Helix

161 – 164

4

Turn

170 – 172

3

Beta strand

177 – 181

5

Helix

189 – 195

7

Helix

206 – 209

4

Turn

210 – 212

3

Helix

217 – 226

10

Helix

228 – 243

16

Turn

244 – 246

3

Sequences

	Sequence		Length	Mass (Da)
	P48534-1 [UniParc]. Last modified January 23, 2007. Version 2. Checksum: 6F51006D0A13B42C	FASTA	250	27,193
	10 20 30 40 50 60 MGKSYPTVSP DYQKAIEKAK RKLRGFIAEK KCAPLILRLA WHSAGTFDSK TKTGGPFGTI 70 80 90 100 110 120 KHQAELAHGA NNGLDIAVRL LEPIKEQFPI VSYADFYQLA GVVAVEITGG PEVPFHPGRE 130 140 150 160 170 180 DKPEPPPEGR LPDATKGSDH LRDVFGKAMG LSDQDIVALS GGHTIGAAHK ERSGFEGPWT 190 200 210 220 230 240 SNPLIFDNSY FTELLTGEKD GLLQLPSDKA LLTDSVFRPL VEKYAADEDV FFADYAEAHL 250 KLSELGFAEA

References

[1]	"Molecular cloning and nucleotide sequence analysis of a cDNA encoding pea cytosolic ascorbate peroxidase." Mittler R., Zilinskas B.A. FEBS Lett. 289:257-259(1991) [PubMed: 1915856] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: cv. Little Marvel. Tissue: Leaf.
[2]	"Molecular cloning and characterization of a gene encoding pea cytosolic ascorbate peroxidase." Mittler R., Zilinskas B.A. J. Biol. Chem. 267:21802-21807(1992) [PubMed: 1400489] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Little Marvel.
[3]	Erratum Mittler R., Zilinskas B.A. J. Biol. Chem. 268:4568-4568(1993)
[4]	"Crystal structure of recombinant pea cytosolic ascorbate peroxidase." Patterson W.R., Poulos T.L. Biochemistry 34:4331-4341(1995) [PubMed: 7703247] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).

Cross-references

Sequence databases

EMBLGenBankDDBJ

M93051 Genomic DNA. Translation: AAA33645.1.
X62077 mRNA. Translation: CAA43992.1.

PIR

A45116.

3D structure databases

PDBMSD

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1APX	X-ray	2.20	A/B/C/D	1-250	[»]

ModBase

Search...

Protein family/group databases

PeroxiBase

2462. PsAPx01.

Family and domain databases

InterPro

IPR002207. Asc_perxdse.
IPR002016. Haem_peroxidase_pln/fun/bac.
[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...

Other Resources

LinkHub

P48534.

Entry information

Entry name

APX1_PEA

Accession

Primary (citable) accession number: P48534

Entry history

Integrated into UniProtKB/Swiss-Prot:	February 1, 1996
Last sequence update:	January 23, 2007
Last modified:	November 25, 2008
This is version 68 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)