BACTERIAL ANTIFERMENTS : STUDIES ON FERMENT ACTION. XVII.

1. Intact bacteria probably resist tryptic digestion because of the absence of an exposed protein substrate. 2. Dried organisms resist digestion in a degree proportional to their content of unsaturated lipoids. 3. Lipoidal extractives reduce the resistance to tryptic digestion. 4. The extracted lipoids (saponified) are antitryptic in a degree proportional to their unsaturation. 5. The inactivation of the antiferment in Gram-negative organisms is probably due to changes in the degree of lipoidal dispersion. 6. Bacteria adsorb lipoids from the serum when incubated at 37 degrees C. Such organisms when dried are found to be more resistant to tryptic digestion than untreated organisms.