RECOGNITION OF PHOSPHATE GROUPS BY IMMOBILIZED ALUMINUM(III) IONS

Aluminium ions, immobilized on iminodiacetate-agarose, were used as a chromatographic adsorbent. At pH 6.0, in strong salt solution, phosphoamino acids, phosphopeptides, phosphoproteins and nucleotides that contained terminally bound phosphate were retained. At pH 7.5 most of the phosphorus compounds were desorbed. Conversely, phosphate-free compounds were unretained at both pHs and the same behaviour was displayed by nucleotides which contained only internally bound phosphate. These findings might be useful as a basis for the development of a procedure for isolating phosphoproteins.