Calcium phosphate amino acid composition

Experimental and Calculated Amino Acid Composition of Micellar Calcium Phosphate ... 

Normal human serum actually contains two chromatographically distinct forms of ceruloplasmin. A calcium phosphate column cleanly separates major (I) and minor (II) components, the latter being approximately 15% of the total ceruloplasmin present in the serum (109—111). Ryden (112, 113) has shown that the two forms though identical in amino acid composition and Cu binding capacity, differ in the degree to which carbohydrate components have been affixed to the protein during biosynthesis. Most of the presently accepted physical properties of human ceruloplasmin are presented in Table 2. 

Bajpai P.K. 1990. Ceramic amino acid composites for repairing traumatized hard tissues. In Handbook of Bioactive Ceramics, Vol. II Calcium Phosphate and Hydroxylapatite Ceramics. T. Yamamuro, L.L. Hench, and J. Wilson-Hench (Eds.), pp. 255-270. CRC Press, Baton Raton, FL. 

Separates aqueous phase without altering the ionic composition. Principally applied in studies on calcium and phosphate in cheese, buffering capacity, lysis of starter cultures Commonly used to extract short peptides and amino acids. Suitable for bacterially ripened cheeses... 

The amino acid and ionic composition of micellar calcium phosphate can be used to estimate the degree of protonation of the phosphate groups. By summing the positive and negative charges, a charge... 

Calcium solubility curves for TPN solutions containing 1.5% (w/v) amino acid and 10% (w/v) dextrose at pH 5.5 are shown in Fig. 10.1. The broken straight lines show the calcium and phosphate concentrations at 3 1 and 2 1 ratios. The dotted curve for Aminosyn solutions shows the concentrations at which precipitation occurs after 18 h at 25°C followed by 30 min in a water bath at 37°C. The full curve is for TrophAmine solutions, and represents calcium or phosphate concentrations at which visual or microscopic precipitation or crystallisation occurs. Compositions to the left of the curves represent physically compatible solutions. 

The stability of the tooth surface to spontaneous dissolution and accretion is primarily mediated by statherin, a 43 amino acid polypeptide encoded by a single gene (Stath) on chromosome 4. Its two N-terminal serine residues spontaneously become phosphory-lated in saliva, and they attach statherin tightly to exposed tooth enamel, preventing dissolution or calcium phosphate accretion. Nevertheless, all proteins in whole saliva adhere to some extent to enamel, forming an acquired pellicle that replaces abraded enamel cuticle (Chap. 9). Differences in amount or composition of the proteins in whole saliva cause differences in acquired pellicle composition. 

The extracellular fluids are essentially solutions of sodium chloride and sodium bicarbonate but they also contain small amounts of calcium, magnesium and potassium, and of phosphate, sulphate and organic ions. Their pH is maintained in the range 7-35-7 45. Organic constituents include glucose, amino acids, urea and a multitude of other compounds in very small amounts. The main difference in composition of the various extracellular fluids lies in their protein contents which range from 7% in plasma down to 0-1% in subcutaneous interstitial fluid. 

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