Reviewed, UniProtKB/Swiss-Prot P85026 (PPO_ZINOF)

Names and origin

Protein names	Recommended name:     Polyphenol oxidase       Short name=PPO     EC=1.10.3.1 Alternative name(s):     Catechol oxidase
Organism	Zingiber officinale (Ginger) (Amomum zingiber)
Taxonomic identifier	94328 [NCBI]
Taxonomic lineage	Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › Liliopsida › Zingiberales › Zingiberaceae › Zingiber

Protein attributes

Sequence length	10 AA.
Sequence status	Fragment.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Catalyzes the oxidation of mono- and o-diphenols to o-diquinones. Ref.1
Catalytic activity	2 catechol + O2 = 2 1,2-benzoquinone + 2 H2O. Ref.1
Cofactor	Binds 2 copper ions per subunit By similarity. UniProtKB Q9ZP19
Subunit structure	Homodimer. Ref.1
Tissue specificity	Expressed in the rhizome. Not detected in leaves. Ref.1
Developmental stage	Expressed throughout rhizome development. Ref.1
Post-translational modification	Glycosylated. Ref.1
Sequence similarities	Belongs to the tyrosinase family.
Biophysicochemical properties	pH dependence: Optimum pH is 4.5. Active from pH 3.0 to 8.0. The activity decreases sharply above pH 7.5. Ref.1 Temperature dependence: Optimum temperature is 60 degrees Celsius. There is only a slight decrease in activity at 75 degrees Celsius and a sharp decrease in activity at 90 degrees Celsius. Ref.1

Ontologies

Keywords
Ligand	Copper Metal-binding
Molecular function	Oxidoreductase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	catechol oxidase activity Inferred from electronic annotation. Source: EC copper 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 – ›10	›10	Polyphenol oxidase		PRO_0000259621
Experimental info
	Non-terminal residue	10	1

Sequences

	Sequence		Length	Mass (Da)
	P85026-1 [UniParc]. Last modified October 31, 2006. Version 1. Checksum: 38286BAAA87862C8	FASTA	10	946
	10 EQGVGGDDGL

References

[1]

"Purification and characterization of a polyphenol oxidase from the rhizome of Zingiber officinale." Joseph A., Thayumanavan B., Manickam A., Panicker P.R. Submitted (SEP-2006) to UniProtKB Cited for: PROTEIN SEQUENCE, FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, SUBUNIT, TISSUE SPECIFICITY, DEVELOPMENTAL STAGE, GLYCOSYLATION. Tissue: Rhizome.

Cross-references

3D structure databases
ModBase	Search...
Enzyme and pathway databases
BRENDA	1.10.3.1. 189688.
Family and domain databases
PROSITE	PS00497. TYROSINASE_1. Partial match. PS00498. TYROSINASE_2. Partial match. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

PPO_ZINOF

Accession

Primary (citable) accession number: P85026

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 31, 2006
Last sequence update:	October 31, 2006
Last modified:	November 24, 2009
This is version 14 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)