Some properties of soluble and solubilized particle-bound hexokinase

Abstract— 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.