Primary Information
BoMiProt ID	Bomi146
Protein Name	Haptoglobin
Organism	Bos taurus
Uniprot ID	Q2TBU0
Milk Fraction	Whey
Ref Sequence ID	NP_001035560.1
Aminoacid Length	401
Molecular Weight	44859
FASTA Sequence	Download
Gene Name	HP
Gene ID	280692
Protein Existence Status	Reviewed: Experimental evidence at transcript level
Secondary Information
Presence in other biological fluids/tissue/cells	serum, saliva, amniotic fluid, urine
Protein Function	antioxidant, scavenger of free hemoglobin and carry them for degradation in the liver and for iron recycling, has angiogenic, anti-inflammatory and immunomodulatory properties; binds to most CD4 and CD8 T lymphocytes, directly inhibiting their proliferation and further modifying the T helper 1/Th2 balance; haptoglobin polymorphism may play a role in susceptibility to bacterial infections in patients with liver cirrhosis. Haptoglobin is an acute phase protein capable of binding haemoglobin, thus preventing iron loss and renal damage.
Biochemical Properties	2 peptides derived from haptoglobin can independently bind to hemoglobin and prevent it from oxidizing substrate; highest binding affinity for hemoglobin; α and ß chains are covalently linked by an intermolecular disulfide bond formed by Cys131 and Cys248; hydrophobic region, adjacent to the Hb-binding site is responsible for the chaperonelike activity of HPT
Significance in milk	significant role in the early response of the mammary gland to pathogenic bacteria;
PTMs	Acidic glycoprotein tetramer; β-chain contains four N-glycosylation sites at Asn184, Asn207, Asn211 and Asn241; increased O-glycosylation like fucosylation was revealed in different diseases; fucosylation and sialylation have been reported to influence ligand–receptor interactions as found in humans
Site(s) of PTM(s) N-glycosylation, O-glycosylation, Phosphorylation
Predicted Disorder Regions	NA
DisProt Annotation
TM Helix Prediction	No TM helices
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