Some Properties of Soluble and Solubilized Particle‐bound Hexokinase¹

Particle‐bound hexokinase of rat brain homogenates was solubilized by successive treatment with 0‐9 M‐NaCl or 003 M‐ATP (pH 8.0) and 0‐5% (w/v) Triton X‐100. This solubilized hexokinase and the soluble hexokinase present in cytoplasm of rat brain homogenates were chromatographed on DEAE‐cellulose and some kinetic properties of the isolated hexokinase peaks were studied. The chromatographic separation was greatly influenced by the EDTA‐concentration of the buffer used. No significant differences were observed in the chromatographic pattern and in the apparent K m ‐values for ATP and glucose and the apparent K t for glucose‐6‐phosphate (versus ATP) between the soluble and particulate hexokinase solubilized by different reagents. On agarose‐electrophoresis the solubilized particulate enzyme migrates as one single band, the soluble hexokinase separates into one major and two minor bands.