Q8R481 · PERL_MESAU
- ProteinLactoperoxidase
- GeneLPO
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids710 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Heme-containing oxidoreductase which catalyzes the conversion of thiocyanate (SCN-) into antimicrobial agent hypothiocyanous acid (OSCN-) in the presence of hydrogen peroxide (H2O2). Also involved in the conversion of iodide (I-) into hypoiodite (IO-) in the presence of H2O2 (By similarity).
Responsible for the inactivation of a wide range of micro-organisms and hence, important component of defense mechanism. May be implicated in airway host defense against infection (By similarity).
May contribute to maintaining an appropriate H2O2 cellular level, therefore protecting cells from H2O2-caused injuries and inflammation (By similarity).
Responsible for the inactivation of a wide range of micro-organisms and hence, important component of defense mechanism. May be implicated in airway host defense against infection (By similarity).
May contribute to maintaining an appropriate H2O2 cellular level, therefore protecting cells from H2O2-caused injuries and inflammation (By similarity).
Miscellaneous
Thiocyanate (SCN-) and hypothiocyanite (OSCN-) are bound in the distal heme cavity. The iodide ion (I-) occupies a position which is stabilized by the interactions with heme moiety, His-224, Arg-370 and Glu-373. Hydrogen peroxide is held between the heme iron and His-224.
Catalytic activity
- 2 a phenolic donor + H2O2 = 2 a phenolic radical donor + 2 H2OThis reaction proceeds in the forward direction.
- thiocyanate + H2O2 + H+ = hypothiocyanous acid + H2OThis reaction proceeds in the forward direction.
- iodide + H2O2 = hypoiodite + H2OThis reaction proceeds in the forward direction.
Cofactor
Protein has several cofactor binding sites:
Note: Binds 1 Ca2+ ion per heterodimer.
Note: Binds 1 heme b (iron(II)-protoporphyrin IX) group covalently per heterodimer.
Features
Showing features for binding site, active site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 223 | heme b (UniProtKB | ChEBI); covalent | ||||
Sequence: D | ||||||
Active site | 224 | Proton acceptor | ||||
Sequence: H | ||||||
Binding site | 225 | Ca2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 299 | Ca2+ (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 301 | Ca2+ (UniProtKB | ChEBI) | ||||
Sequence: F | ||||||
Binding site | 303 | Ca2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 305 | Ca2+ (UniProtKB | ChEBI) | ||||
Sequence: S | ||||||
Site | 370 | Transition state stabilizer | ||||
Sequence: R | ||||||
Binding site | 373 | heme b (UniProtKB | ChEBI); covalent | ||||
Sequence: E | ||||||
Binding site | 466 | Fe (UniProtKB | ChEBI) of heme b (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | basolateral plasma membrane | |
Cellular Component | cytoplasm | |
Cellular Component | extracellular space | |
Molecular Function | heme binding | |
Molecular Function | lactoperoxidase activity | |
Molecular Function | metal ion binding | |
Molecular Function | peroxidase activity | |
Molecular Function | thiocyanate peroxidase activity | |
Biological Process | defense response to bacterium | |
Biological Process | detection of chemical stimulus involved in sensory perception of bitter taste | |
Biological Process | response to oxidative stress |
Keywords
- Molecular function
- Ligand
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended nameLactoperoxidase
- EC number
- Short namesLPO
- Alternative names
Gene names
Organism names
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Glires > Rodentia > Myomorpha > Muroidea > Cricetidae > Cricetinae > Mesocricetus
Accessions
- Primary accessionQ8R481
Proteomes
PTM/Processing
Features
Showing features for signal, propeptide, glycosylation, chain, disulfide bond, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Signal | 1-22 | |||||
Sequence: MKVLLRLPALLASLTLLQMAAS | ||||||
Propeptide | PRO_0000433299 | 23-98 | ||||
Sequence: TRNATRTATIRETVDEVKVQVNKAFLDSRDRLKTDMSNLAPTVRHLSGYLKQAKGRTRTAIRVGQVWEQSLKRLRR | ||||||
Glycosylation | 25 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Chain | PRO_0000433300 | 99-710 | Lactoperoxidase | |||
Sequence: MVPLTNVTGQGLDLTSLSWEVGCGHPAPTVTCNISNPYRTITGDCNNRKNPELGSANRALARWLPAEYEDGLSLPFGWTPGKTRNGFPLPQPRDVSNQVLDYLNEEEILDQNRSLLFMQWGQIVDHDLDFAPETEMGSDNYSKAQCDELCIQGDNCFPIMFPKGDPKLKTQGKCLPFFRAGFVCPTSPYQSLAREQINALTSFMDASMVYGSEPSLANRLRNLSSPLGLMAVNEEVSDHGRPLLPFVNVKPSPCEVINRTAGVPCFLAGDSRASEQILLATSHTLFLREHNRLARELSRLNPQWDGEKLYQEARRIMGALIQIITFRDYLPILLGDELQKWIPPYQGYKETVDPRISNVFTFAFRFGHLEVPSTVSRLDENYQPWGSEPELPLHKLFFNTWRVVKDGGIDPLVRGLLAKKAKLAHQDKMMTGELRNMLFQPNHTVHGFDLAAINIQRCRDHGQPGYNSWRAFCGLSQPKTLEELSAVLRNEVLAKKLMDLYGTPDNIDIWLGAIAEPLVRRGRVGPLLTCLLGQQFQRIRDGDRFWWENPGVFTEKQRDSLQKMSFSRLVCDNTGINKVPLNPFQPNSYPHSFVDCSAIEKLDLTPWASVKK | ||||||
Glycosylation | 104 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Disulfide bond | 130↔143 | |||||
Sequence: CNISNPYRTITGDC | ||||||
Glycosylation | 131 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Glycosylation | 238 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Disulfide bond | 244↔254 | |||||
Sequence: CDELCIQGDNC | ||||||
Disulfide bond | 248↔272 | |||||
Sequence: CIQGDNCFPIMFPKGDPKLKTQGKC | ||||||
Modified residue | 313 | Phosphoserine | ||||
Sequence: S | ||||||
Glycosylation | 320 | N-linked (GlcNAc...) asparagine | ||||
Sequence: N | ||||||
Disulfide bond | 352↔363 | |||||
Sequence: CEVINRTAGVPC | ||||||
Modified residue | 480 | 3'-nitrotyrosine | ||||
Sequence: Y | ||||||
Disulfide bond | 571↔628 | |||||
Sequence: CGLSQPKTLEELSAVLRNEVLAKKLMDLYGTPDNIDIWLGAIAEPLVRRGRVGPLLTC | ||||||
Disulfide bond | 669↔694 | |||||
Sequence: CDNTGINKVPLNPFQPNSYPHSFVDC |
Keywords
- PTM
PTM databases
Expression
Tissue specificity
Expressed in the lacrimal gland with higher levels and 3-fold higher activity in adult females than males and secreted into tears (at protein level).
Induction
Repressed by the androgen dihydrotestosterone (DHT) and the estrogen estradiol (E2) (at protein level).
Interaction
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length710
- Mass (Da)80,219
- Last updated2002-06-01 v1
- ChecksumAD8C9359DB1C270F
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AF498045 EMBL· GenBank· DDBJ | AAM15535.1 EMBL· GenBank· DDBJ | mRNA |