Search by BoMiProt ID - Bomi102

Primary Information

BoMiProt ID Bomi102
Protein Name Beta-2-microglobulin
Organism Bos taurus
Uniprot IDP01888
Milk FractionWhey
Ref Sequence ID NP_776318.1
Aminoacid Length 118
Molecular Weight 13677
FASTA Sequence Download
Gene Name B2M
Gene ID 280729
Protein Existence Status Reviewed: Experimental evidence at protein level

Secondary Information

Presence in other biological fluids/tissue/cells human urine, plasma, and cerebrospinal fiuid.
Protein Function Component of class 1 MHC ; its presence is necessary for posttranslational processing and insertion of HLA heavy chains into the membrane; stabilize the structure of the heavy chain and its removal causes loss of alloantigenic sites on HLA; the MHC class I antigens, in complex with ,ß2m, participate in specific recognition and functional events involving both foreign antigens and receptors on cytotoxic T-cell lymphocytes; major protein constituent of the amyloid fibrils in Hemodialysis-associated amyloidosis. beta 2-microglobulin acts as a modulator of lymphocyte surface and as a potential regulator of the immune system.
Biochemical Properties human ß2-microglobulin is monomeric in solution; sedimentation coefficient is 1.65S; cntains one cystine residue per monomer and no free sulfhydryl groups were detected; closely resembles the constant domains of Ig with significant differences only in the polypeptide loops connecting the p structures
Significance in milk highest at the beginning of lactation; transmission of humoral immunity from a mother to her young in the mouse occurs mostly postnatally by the uptake of IgG from maternal milk into the pup’s systemic circulation. IgG binds to the brush borders of jejunal epithelial cells which fails to happen if ß2M gene is dirupted
PTMs incubating normal ß2M with glucose produces advanced glycatione end products that make ß2M more acidic- promotes amyloidosis
Site(s) of PTM(s)

N-glycosylation, O-glycosylation,
SCOP Class : All beta proteins
Fold : Immunoglobulin-like beta-sandwich
Superfamily : Immunoglobulin (Ig) domain-like
Family : C1 set domains-like
Domain Name : 1BMG A:1-98

CATH Matched CATH superfamily
Predicted Disorder Regions (31-37)
DisProt Annotation
TM Helix Prediction No TM helices
PDB ID 1BMG, 2XFX, 3L9R, 3PWV, 4F7C, 4F7E, 4IIQ, 4L8S, 4L9L, 4LCC,
Bibliography 1. Miyata, T., Oda, O., Inagi, R., Iida, Y., Araki, N., Yamada, N., … Kinoshita, T. (1993). β2-Microglobulin modified with advanced glycation end products is a major component of hemodialysis-associated amyloidosis. Journal of Clinical Investigation, 92(3), 1243–1252.
2. Groves, M. L., & Greenberg, R. (1977). Bovine homologue of beta2-microglobulin isolated from milk. Biochemical and Biophysical Research Communications, 77(1), 320–327.
3. Becker, J. W., & Reeke, G. N. (1985). Three-dimensional structure of β 2 -microglobulin. Proceedings of the National Academy of Sciences of the United States of America, 82(12), 4225–4229.
4. Berggård, I., & Bearn, A. G. (1968). Isolation and properties of a low molecular weight beta-2-globulin occurring in human biological fluids. The Journal of Biological Chemistry, 243(15), 4095–4103. Retrieved from 5.Bernier GM. beta 2-Microglobulin: structure, function and significance. Vox Sang. 1980 Jun;38(6):323-7. doi: 10.1111/j.1423-0410.1980.tb04500.x. PMID: 6159720.