STUDIES ON THE ENZYMES OF PNEUMOCOCCUS : III. CARBOHYDRATE-SPLITTING ENZYMES: INVERTASE, AMYLASE, AND INULASE

J Exp Med. 1920 Oct 31;32(5):583-93. doi: 10.1084/jem.32.5.583.

Abstract

1. A method is described for the preparation of an active enzyme-containing solution of pneumococci, in which no living cells are present. These enzymes are capable of hydrolyzing sucrose, starch, and inulin. 2. The invertase and amylase of pneumococcus are active within the limits pH 5 to 8, with an optimum reaction of about pH 7. This reaction range corresponds closely with limiting hydrogen ion concentrations which define growth of the organism in the presence of carbohydrate. 3. These studies indicate that the enzymes described are not true secretory products of the living cell, but are of the nature of endoenzymes, since their activity can be demonstrated only when cell disintegration has occurred.