MECHANISM OF THE LYSIS OF PNEUMOCOCCI BY FREEZING AND THAWING, BILE, AND OTHER AGENTS.

PNEUMOCOCCI, LIVING OR DEAD, ARE SOLUBLE IN BILE WHEN: (a) the autolytic enzymes are still present in a potentially active form; (b) conditions are favorable for enzymatic action. Bile solubility of pneumococci involves as a necessary step one, or a few, of the many stages of the autolytic complex. These observations hold true for the disruption of pneumococci by freezing and thawing, by previous desiccation with cold acetone, and by dilute solutions of antiseptics. A possible mechanism is discussed to account for these forms of lysis.