Serotransferrin human

Figure 5.1 Schematic diagram of the lactoferrin molecule. The positions of carbohydrate attachment are marked with a star. O, ovotransferrin T, human serotransferrin L, human lactoferrin R, rabbit serotransferrin M, melanotransferrin A, the connecting helix B, the C-terminal helix. The disulfide bridges are indicated by heavy bars, and the iron and carbonate binding sites by filled or open circles, respectively. Reprinted from Baker et al., 1987. Copyright (1987), with permission from Elsevier Science.

H-N.m.r. Data far Anomeric Protons, Mannose H-2, and N-Acetyl Methyl Protons of Human Serotransferrin Asialoglycan (from Ref. 191)... 

Serotransferrins. All known serotransferrins contain one or two glycans of the A-acetyllactosaminic type which are located in the C-terminal lobe of the polypeptide chain. Hen [102], rabbit [103,104], pig [105] and rat [67] serotransferrins contain a single glycan located in a very similar position which does not correspond to Asn-413 in human serotransferrin (Fig. 2). 

Fig. 3. Location and molecular masses from 79 260 to 81 519 of human serotransferrin glycovariants. Open circle, NeuAc solid square, Gal solid circle, GlcNAc solid diamond, Man 1 to 679, amino acids of the peptide chain xSA, number of sialic acid residues [112],...

Fig. 5. Schematic representation of the human serotransferrin receptor. C, cysteine residues positions 89 and 98, disulfide bridges position 62, fatty acid chain. From Trowbridge et al. [122].

Fig. 6. Primary structure of serotransferrin diantennary glycans from human (A,B) [211-213], cow (A,B) [119, 214], rabbit (A) [103], sheep (A) [119,215], marsupial (kangaroo, opossum, wallaby) (A) [119,216], Primary structure of human serotransferrin triantennary glycans (C,D) [119-217],...

Liver diseases. By applying the crossed affino-electrophoresis method, Spik et al. [255,256] have demonstrated that the human serotransferrin glycans are profoundly modified in liver diseases such as viral hepatitis and alcoholic cirrhosis with a marked increase of triantennary glycans (see also refs. [257-259]). 

Fig. 18. Primary structure of tetra- and pentaantennary glycans from human serotransferrin secreted into culture medium of human hepatocarcinoma cell line Hep G2. The a-l,3-linked fucose residue is conjugated to the GlcNAc of one of the antennae [261]. R, GlcNAc(pi )[Fuc(al-6)]o iGlcNAc(p-N)Asn.

Fig. 19. Primary structure of the glycan from human serotransferrin isolated from a patient with carbohydrate-deficient syndrome (CDG) type II [265,268], R, GIcNAc(pi-4)GIcNAc(pi-N)Asn.

The human serotransferrin contains two carbohydrates of the N-acetyllactosaminic type, located in the C-terminal lobe of the polypeptide chain. The two glycosylation sites (Asn-413 and 611) may be occupied by bi-, tri- and tetra-antennary carbohydrates. 

Carbohydrates of human serotransferrin are not fucosylated, while those of human lactotransferrin have an a-l,6-fucose bound to the N-acetylglucosamine residue linked to the peptide chain, and an a-l,3-fucose bound to the N-acetyllactosamine residues. 

Two structures [(53) and (54)1 are proposed for the unique glycan of hen egg-white ovotransferrin. A comparative study of this glycan with those of human serotransferrin and lactotransferrin reveals profound differences that could form the basis for the specificity of recognition of target cells by these glycoproteins. 

The extents of sialylation of eleven plasma hydrolases have been examined. Most plasma hydrolases e.g. a-L-fucosidase and a-D-mannosidase) were eluted from DEAE-cellulose at a lower salt concentration after treatment with neuraminidase, although the elution profiles of p-D-glucosidase, P-D-xylosidase, and acid phosphatases were unaffected, indicating that they are less susceptible to the action of neuraminidase. The structure (9) assigned (G. Spick, B. Bayard, B. Fournet, and G. Strecker, F.E.B.S. Letters, 1975, 50, 296) to the carbohydrate component of human serotransferrin has been confirmed by high-resolution H n.m.r. spectroscopy. Electrophoresis separated human serotransferrin into four molecular forms that contain different proportions of bound iron. The nature of the interaction of renins from human and rabbit kidneys with immobilized concanavalin A, and their subsequent desorption with methyl a-D-mannopyrano-side, suggested that both proteins are glycosylated. ... 

Purified rabbit serotransferrin has been shown to contain one glycan chain per molecule, in contrast to human serotransferrin which contains two such chains. Heterogeneity of the glycan moiety of the rabbit glycoprotein was observed from the isolation of a disialyl- and a monosialyl-glycopeptide. The... 

The structure and function of the iron transport protein human serotransferrin have been reviewed recently with special reference to the role of the metal. The nature of the two Fe -binding sites has been investigated by means of resonance Raman (with Fe, Cu, Co , and and e.s.r. spectroscopy (with Cu, -Feiii 66 Cfiii 66 ) and the evidence is now overwhelming that the two... 

Chasteen, D, (1977) Human serotransferrins structure and function. Coord. Chem, Revs. 22 1-36. 

White LK, Chasteen ND. 1979. Q-band electron paramagnetic resonance study of va-nadyl(IV)-labeled human serotransferrin. J Phys Chem 14 279-284. 

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