The amylase of Clostridium acetobutylicum.

The purification and concentration of enzymes by adsorption on charcoal, tannin, aluminum hydroxide, ion exchange resins, and so forth, has been an established practice in the laboratory. Some years before this work was done in 1949, alkali-cooked lignin was used as an adsorbent for mold and malt amylase (Wallerstein et al., 1945). In this paper is described our study of the adsorption of the amylase of Clostridium acetobutylicum on alkali-cooked lignin and charcoal, elution of the enzyme from the adsorbents, and the underlying relationships governing the adsorption. General considerations. With treatment time and temperature fixed, the relationship between the amount of adsorbate taken up and the amount of adsorbent used is frequently given by the empirically derived Freundlich equation (Bull, 1943): X/M = kC"', where X represents the units of enzyme held by the adsorbent, ll is the weight of adsorbent used, C is the concentration of enzyme remaining unadsorbed, and k and n are constants determined by the nature of the enzyme and adsorbent and the conditions of adsorption. Thus, the Freundlich equation correlates the adsorptive capacity per unit weight adsorbent (X/IM) with the concentration of adsorbate remaining in solution (C). The slope of the Freundlich e(quation on a loglog plot is 1/n, which is an index of the ease or difficulty with which the enzyme is adsorbed. The Langmuir equation has been derived from adsorption in a layer one molecule thick. If a straight line results from plotting C against C/M, the adsorption may be assumed to be proceeding according to the assumptions in the derivation of the Langmuir equation.