MECHANISM OF GRAM STAIN REVERSAL

Abstract
The action of oxidizing or acidic agents, such as picric acid or ribonuclease, on the Gram-positive Bacillus cereus and of reducing or alkaline agents such as gentian violet, Na bisulfite, NaOH, on the Gram-negative Escherichia coli, or on B. cereus rendered Gram-negative, produces a reversal of Gram stain behavior similar to that previously found to occur with wool. The mechanism used to explain the staining behavior of wool is also used to explain the staining behavior of bacteria. Apparent exceptions are discussed in the light of the theory offered.