Rabbit serotransferrin

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.

Structural comparison of the iron binding sites of N-lobe of rabbit serotransferrin, human lactotransferrin and... 

As mentioned above (see section 2.2.1), the three-dimensional structure of the peptide chains of rabbit serotransferrin, of human and bovine lactotransferrins and of ovotrans-... 

As mentioned above. X-ray diffraction of transferrin furnishes little information on the 3D-structure of the glycans and the images we have today remain largely speculative since they result from molecular modelling studies. We have represented in Fig. 21 the 3D-structure, determined by molecular modelling on the basis of X-ray diffraction data of rabbit serotransferrin [276] and of human lactotransferrin [89,92]. In rabbit serotransferrin, the single glycan linked to the peptide chain is immobilized into only... 

Fig. 21. Molecular modelling (A,B) of rabbit serotransferrin glycan and (C) of human lactotransferrin [192, 210,275] (A) 3D structure of rabbit serotransferrin (B) interaction of rabbit serotransferrin glycan in a broken-wing conformation with a peptide segment (amino acids 254 to 271) in an a-helix conformation, 7,7, Al-acetylneuraminic acid residues (see Fig. 6A). (C) 3D structure of human lactotransferrin. Arrows indicate the position of glycans.

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... 

Some glycopeptides from rabbit serotransferrin have been isolated and characterized. ... 

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. 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],...

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. ... 

Figure 5. Plasma Iron and Total Iron Binding Capacity (TIBC) of Rabbit Plasma Before and After Infection with Pasteurella Multocid,a. Percentages at Top of Bars Indicate Percent Saturation of Serotransferrin with Iron. Reprinted with Permission from Kluger and Rothenburg (1979). Copyright by American Association for the Advancement of Science.

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