Albumin glycosylated

Albumin, which is not glycosylated, is the major protein and is the principal determinant of intravascular osmotic pressure it also binds many Hgands, such as drugs and bilirubin. 

Albumin, tetanus toxin, autocrine motility factor, interleukin-2, alkaline phosphatase, glycosyl-phosphatidylinositol (GPI)-GFP, polyoma virus, and echo virus 1 (26). 

The most frequent protein in the plasma, at around 45 g is albumin. Due to its high concentration, it plays a crucial role in maintaining the blood s colloid osmotic pressure and represents an important amino acid reserve for the body. Albumin has binding sites for apolar substances and therefore functions as a transport protein for long-chain fatty acids, bilirubin, drugs, and some steroid hormones and vitamins. In addition, serum albumin binds Ca "" and Mg "" ions. It is the only important plasma protein that is not glycosylated. 

Sugars substituted by a functionalized fluoroalkyl chain have been used to glycosylate proteins, such as albumin (BSA, HSA) and haptenes. In the latter case, the fluorine atoms can be used as probes in F NMR to determine quantitatively the bonding of the haptene. " ... 

Using tunicamycin, Struck and coworkers203 demonstrated that, despite the inhibitory effect of the drug on glycosylation, secretion of transferrin, serum albumin, and apoproteins A and B of VLDL by primary cultures of rat and chick hepatocytes was virtually unimpaired. Keller and Sivank204 demonstrated the same point by showing that,... 

Nishikawa, M., Ohtsubo, Y., Ohno, J., Fujita, T., Koyama, Y., Yamashita, F., Hashida, M. and Sezaki, H. (1992) Pharmacokinetics of receptor-mediated hepatic uptake of glycosylated albumin in mice. Int.J. Pharm., 85, 75-85. 

Apart from hemoglobin, various other proteins have been shown to be glycosylated by one of the methods described above. With the exception of insulin and albumin, however, the specific glyco-sylation sites remain to be elucidated. 

No alteration of protein half-life has been detected with glycosylated albumin (39) and ferritin (51). However, Jones and Peterson (45) found that fibrinogen survival, which was reduced in diabetic patients with elevated glycemia, could be increased to normal value shortly after insulin therapy. This suggests that a labile Schiff base could play a role in the regulation of fibrinogen turnover. 

The three antisera and the anti-glycosyl antibodies isolated from these antisera have been tested in agar diffusion tests for cross-reactivity with the three iirmunogens and with bovine serum albumin. These results are shown in Figure 8. 

Recently, a similar glycosylation has also been reported in human serum albumin. Approximately 6-15% of the albumin was found to exist naturally in the glycosylated form (54). In this case lysine residues rather than just the N-terminal ct-N groups were shown to be involved in the reaction. Since the extent of these reactions appears to reflect the glucose concentration in the environment of the glycosylated proteins, their use as diagnostic indicators in diabetes is being explored. 

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