In vitro investigation reveals competitive selection drives nonsmooth variant emergence in Brucella abortus, indicating metabolite-influenced population dynamics.
Key Points
To examine the mechanisms by which metabolic products and natural selection govern the emergence and establishment of nonsmooth mutant variants in prolonged cultures of Brucella abortus.
Monitored Brucella abortus populations in smooth broth cultures over prolonged incubation intervals.
Tracked bacterial population dynamics using plate counts for viable cells and direct counts for total cell density.
Assessed competitive selection between spontaneous mutants and wild-type cells across distinct growth phases.
Spontaneous undirected mutants emerge at low frequencies and establish dominance in cultures primarily after competitive conditions develop.
Competitive advantages manifest as viable cell populations peak relative to total cell counts, driving orderly and cyclic replacements of parental smooth strains by nonsmooth variants.