Recombinant Human Alpha 1 microglobulin protein (GST tag N-Terminus)

Specifications

Form

Liquid

General info

Function

Alpha-1-microglobulin. Antioxidant and tissue repair protein with reductase, heme-binding and radical-scavenging activities. Removes and protects against harmful oxidants and repairs macromolecules in intravascular and extravascular spaces and in intracellular compartments (PubMed : 11877257, PubMed : 15683711, PubMed : 22096585, PubMed : 23157686, PubMed : 23642167, PubMed : 25698971, PubMed : 32092412, PubMed : 32823731). Intravascularly, plays a regulatory role in red cell homeostasis by preventing heme- and reactive oxygen species-induced cell damage. Binds and degrades free heme to protect fetal and adult red blood cells from hemolysis (PubMed : 11877257, PubMed : 32092412). Reduces extracellular methemoglobin, a Fe3+ (ferric) form of hemoglobin that cannot bind oxygen, back to the Fe2+ (ferrous) form deoxyhemoglobin, which has oxygen-carrying potential (PubMed : 15683711). Upon acute inflammation, inhibits oxidation of low-density lipoprotein particles by MPO and limits vascular damage (PubMed : 25698971). Extravascularly, protects from oxidation products formed on extracellular matrix structures and cell membranes. Catalyzes the reduction of carbonyl groups on oxidized collagen fibers and preserves cellular and extracellular matrix ultrastructures (PubMed : 22096585, PubMed : 23642167). Importantly, counteracts the oxidative damage at blood-placenta interface, preventing leakage of free fetal hemoglobin into the maternal circulation (PubMed : 21356557). Intracellularly, has a role in maintaining mitochondrial redox homeostasis. Bound to complex I of the respiratory chain of mitochondria, may scavenge free radicals and preserve mitochondrial ATP synthesis. Protects renal tubule epithelial cells from heme-induced oxidative damage to mitochondria (PubMed : 23157686, PubMed : 32823731). Reduces cytochrome c from Fe3+ (ferric) to the Fe2+ (ferrous) state through formation of superoxide anion radicals in the presence of ascorbate or NADH/NADPH electron donor cofactors, ascorbate being the preferred cofactor (PubMed : 15683711). Has a chaperone role in facilitating the correct folding of bikunin in the endoplasmic reticulum compartment (By similarity).. Inter-alpha-trypsin inhibitor light chain. Kunitz-type serine protease inhibitor and structural component of extracellular matrix with a role in extracellular space remodeling and cell adhesion (PubMed : 20463016, PubMed : 25301953). Among others, has antiprotease activity toward kallikrein, a protease involved in airway inflammation; inhibits GZMK/granzyme, a granule-stored serine protease involved in NK and T cell cytotoxic responses; and inhibits PLG/plasmin, a protease required for activation of matrix metalloproteinases (PubMed : 10480954, PubMed : 15917224, PubMed : 16873769). As part of I-alpha-I complex, provides for the heavy chains to be transferred from I-alpha-I complex to hyaluronan in the presence of TNFAIP6, in a dynamic process that releases free bikunin and remodels extracellular matrix proteoglycan structures. Free bikunin, but not its heavy chain-bound form, acts as potent protease inhibitor in airway secretions (PubMed : 16873769). Part of hyaluronan-rich extracellular matrix that surrounds oocyte during cumulus oophorus expansion, an indispensable process for proper ovulation (By similarity). Also inhibits calcium oxalate crystallization (PubMed : 7676539).. Trypstatin. Kunitz-type serine protease inhibitor. Has high catalytic efficiency for F10/blood coagulation factor Xa and may act as an anticoagulant by inhibiting prothrombin activation. Inhibits trypsin and mast cell CMA1/chymase and tryptase proteases.

Sequence similarities

In the N-terminal section; belongs to the calycin superfamily. Lipocalin family.

Post-translational modifications

The precursor is proteolytically processed into separately functioning proteins.. Alpha-1-microglobulin. Proteolytically cleaved in the presence of oxyhemoglobin or MPO (PubMed:11877257, PubMed:25698971). The cleaved form t-alpha-1-microglobulin lacks the C-terminal tetrapeptide LIPR and is released from IgA-alpha-1-microglobulin complex as well as from free alpha-1-microglobulin when exposed to oxyhemoglobin or erythrocyte membranes. The cleavage of IgA-alpha-1-microglobulin complex is associated with the reduction of the covalent bond between IgA and alpha-1-microglobulin, yielding an intact IgA molecule (PubMed:11877257). The cleavage by MPO is associated with the transfer of heme group from MPO to t-alpha-1-microglobulin (PubMed:25698971). t-alpha-1-microglobulin has higher reductase activity when compared with full length protein (PubMed:15683711).. Alpha-1-microglobulin. 3-hydroxykynurenine, an oxidized tryptophan metabolite that is common in biological fluids, reacts with Cys-53, Lys-111, Lys-137, and Lys-149 to form heterogeneous polycyclic chromophores including hydroxanthommatin. The reaction by alpha-1-microglobulin is autocatalytic; the human protein forms chromophore even when expressed in insect and bacterial cells. The chromophore can react with accessible cysteines forming non-reducible thioether cross-links with other molecules of alpha-1-microglobulin or with other proteins such as Ig alpha-1 chain C region 'Cys-352'.. Inter-alpha-trypsin inhibitor light chain. Heavy chains are interlinked with bikunin via a chondroitin 4-sulfate bridge to the C-terminal aspartate.. Inter-alpha-trypsin inhibitor light chain. Proteolytically cleaved by PRSS3 at Kunitz domain 2.. N-glycosylated. N-glycan heterogeneity at Asn-115: Hex5HexNAc4 (major), Hex6HexNAc5 (minor) and dHex1Hex6HexNAc5 (minor). N-glycan at Asn-250: Hex5HexNAc4.. O-glycosylated. O-linkage of the glycosaminoglycan, chondroitin sulfate, at Ser-215 allows cross-linking between the three polypeptide chains.