Phosphorylation of human serum albumin and haemoglobin

Chemical phosphorylation of food proteins: an overview and a prospectus

“…The pH is kept constant by adding sodium hydroxide and the temperature is controlled (usually in an ice bath). The following proteins have been phosphorylated with POCl3 in an aqueous system: casein (Neuberg and Oertel, 1914;Rimington, 1927;Boursnell et al, 1948;Matheis et al, 1983b), lactalbumin (Neuberg and Pollack, 1910), j8-lactoglobulin (Woo et al, 1982), ovalbumin (Heidelberger et al, 1941), serum albumins (Mayer and Heidelberger, 1946;Boursnell et al, 1948;Salak et al, 1965), serum globulins (Neuberg and Oertel, 1914;Rimington, 1927;Boursnell et al, 1948), and hemoglobin (Salak et al, 1965). The amount of phosphorus introduced is shown in Table I.…”

“…Using these methods, it has been established that the phosphorus can be attached to hydroxyl oxygen, amino nitrogen, and imidazole nitrogen (Table II). Tyrosyl groups were found to be either phosphorylated only to a limited extent (Mayer and Heidelberger, 1946;Ferrel et al, 1948) or not phosphorylated at all (Taborsky, 1958;Salak et al, 1965). Phosphorus bound to sulfhydryl groups, carboxyl groups, or peptide bonds could not be detected by Ferrel et al (1948).…”

“…Matheis et al, 1983b). Even at neutral pH, phosphorylated proteins containing nitrogen-bound phosphate lose part of their phosphate in aqueous solution at 2-37 °C (Rathlev and Rosenberg, 1956;Taborsky, 1958;Salak et al, 1965;Woo et al, 1982;Matheis et al, 1983b). Therefore, phosphorylated proteins containing acid-stable oxygenbound phosphate are more desirable for incorporation into foods.…”

Effect of chemical phosphorylation on solubility of buffalo milk proteins

“…In the present study up to 6 mol of additional phosphorus was incorporated in WPC upon chemical phosphorylation. A high extent of phosphorylation (mol/mol), 7.1, 13.8 and 50.0 for a-lactalbumin, b-lactoglobulin and serum albumin, has been reported by Neuberg and Pollack (1910), Woo et al (1982), and Salak, Vodrazka, and Cejka (1965), respectively, and the difference in extent of phosphorylation could be due to the variation in the POCl 3 to protein ratio and pH of reaction.…”

Specific limited hydrolysis and phosphorylation of food proteins for improvement of functional and nutritional properties

“…Matheis and Whitaker (43) also covalently attached phosphate groups to proteins by reductive alkylation with glyceraldehyde 3-phosphate. Phosphorylated casein and phosphorylated lysozyme adsorbed more water at 43% relative humidity and 25 C than did control casein (42); however, decreased water solubility was reported (42,47), possibly as a result of cross linking of the protein.…”