Introduction. Kyes and Sachs (1) in 1903 found that acidification of cobra lysin increased its thermostability. This finding was confirmed and extended by Morgenroth and Pane (2). Ando and Nishimura (3) observed recently that the heat stability of diphtheria toxin depended on the acidity, and that the acidified toxin withstood higher temperatures.
On the other hand, several investigators failed to observe any increase of thermostability of lysins after acidification. Famulener and Madsen (4) in a careful quantitative study found that both acidification and alkalization decreased the stability of tetanolysin to heat. Neill (5) did not observe any increase in the thermostability of lysin of B. welchii at pH's ranging between 3 and 9.
The present investigation is a continuation of these studies with reference to the effect of acidification and alkalization on the thermostability and oxidizability of tetanolysin.
Experimental. Methods. Tetanolysin; preparation and titration. Tetanolysin adjusted to various pH's was heated and was then neutralized and titrated.