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° C. Such organisms when dried are found to be more resistant to tryptic digestion than untreated organisms.