LMPD Database


UniProt Annotations

Entry Information
Gene Namearachidonate 15-lipoxygenase, type B
Protein EntryLX15B_HUMAN
UniProt IDO15296
Comment typeDescription
Alternative ProductsEvent=Alternative splicing; Named isoforms=4; Name=A; Synonyms=15-LOb1; IsoId=O15296-1; Sequence=Displayed; Name=B; Synonyms=15-LOX2sv-b; IsoId=O15296-2; Sequence=VSP_003142, VSP_003143; Name=C; Synonyms=15-LOX2sv-c; IsoId=O15296-3; Sequence=VSP_003144, VSP_003145; Name=D; Synonyms=15-LOX2sv-a, 15-LOb2; IsoId=O15296-4; Sequence=VSP_003142;
Biophysicochemical PropertiesKinetic parameters: KM=1100 uM for arachidonate (isoform D at pH 7.4 and 20 degrees Celsius) ; KM=10 uM for linoleate (isoform A at pH 7.4 and 20 degrees Celsius) ; KM=25 uM for arachidonate (isoform A at pH 7.4 and 20 degrees Celsius) ; Vmax=4 umol/min/mg enzyme with arachidonate as substrate (isoform A at pH 7.4 and 20 degrees Celsius) ; Vmax=2 umol/min/mg enzyme with arachidonate as substrate (isoform D at pH 7.4 and 20 degrees Celsius) ; Vmax=4 umol/min/mg enzyme with linoleate as substrate (isoform A at pH 7.4 and 20 degrees Celsius) ;
Catalytic ActivityArachidonate + O(2) = (5Z,8Z,11Z,13E)-(15S)- 15-hydroperoxyicosa-5,8,11,13-tetraenoate.
Catalytic ActivityLinoleate + O(2) = (9Z,11E)-13- hydroxyoctadeca-9,11-dienoate.
CautionDespite its homology with mouse Alox8 (AC O35936), it seems not to have any 8S-lipoxygenase activity on arachidonate.
CofactorName=Fe cation; Xref=ChEBI
DomainThe PLAT domain can bind calcium ions; this promotes association with membranes.
FunctionNon-heme iron-containing dioxygenase that catalyzes the stereo-specific peroxidation of free and esterified polyunsaturated fatty acids generating a spectrum of bioactive lipid mediators. Converts arachidonic acid to 15S- hydroperoxyeicosatetraenoic acid/(15S)-HPETE. Also acts on linoleic acid to produce 13-hydroxyoctadecadienoic acid/13-HPODE. Has no detectable 8S-lipoxygenase activity but reacts with (8S)- HPETE to produce (8S,15S)-diHPETE. May regulate progression through the cell cycle and cell proliferation. May also regulate cytokine secretion by macrophages and therefore play a role in the immune response. May also regulate macrophage differentiation into proatherogenic foam cells. {ECO
InductionUp-regulated by UV-irradiation.
PathwayLipid metabolism; hydroperoxy eicosatetraenoic acid biosynthesis.
Sequence CautionSequence=AAD37786.1; Type=Erroneous gene model prediction; Evidence= ;
SimilarityBelongs to the lipoxygenase family.
SimilarityContains 1 lipoxygenase domain. {ECO
SimilarityContains 1 PLAT domain. {ECO
Subcellular LocationCytoplasm, cytosol. Cell membrane. Cytoplasm, cytoskeleton. Membrane; Peripheral membrane protein. Note=Predominantly cytosolic; becomes enriched at membranes upon calcium binding.
Subcellular LocationIsoform A
Tissue SpecificityExpressed in hair, prostate, lung, ovary, lymph node, spinal cord and cornea. {ECO