THE NATURE OF THE EFFECT OF α-ALANINE ON POPULATION CHANGES OF BRUCELLA

Abstract

The inhibitory effects of D- or DL- [alpha][long dash]alanine upon smooth cells of B. abortus lead to population changes involving the establishment of more alanine resistant, usually antigenically different mutants. These effects appear to involve an interference with pantothenic acid synthesis or utilization. This is indicated by observations on the effects of increased pantothenate levels in the media, the effects of partial depletion of intracellular pantothenic acid, and the activity of known inhibitors of pantothenic acid synthesis, including salicylate and of certain analogues of pantothenic acid. Additional indirect evidence is provided by the finding that many streptomycin resistant mutants simultaneously display increased resistance to the D-isomer of [alpha]-alanine.