The Endogenous Respiration of Bacillus cereus

Abstract

Measurements were made of the rate of respiration by cells of B. cereus suspended in salt solns. Low concs. of salts increased the rate of respiration; high concs. decreased it. Sugars, when not fermented, did not bring about similar changes. The increased respiration of dilute saline suspensions was found to depend on the cation of the salt present: mono-, di-, and tri-valent cations were equally effective at concs. roughly in the ratio 1000:100:1. In suspensions with high concs. of salts (of the order 1-2M), the rate of respiration was reduced exponentially with increase in salt conc. Both cations and anions played a part in this inhibition. In their inhibitory action on respiration, no antagonism was observed between Na nd Ca chlorides.