Bright luminescence of Vibrio fischeri aconitase mutants reveals a connection between citrate and the Gac/Csr regulatory system

• DOI: 10.1111/mmi.12864
• Publication Date: 2014-11-17T13:50:39Z
• Authors: Alecia N. Septer; Jeffrey L. Bose; Anna Lipzen; Joel Martin; Cheryl Whistler; Eric V. Stabb
• Keywords: Aconitate Hydratase; 0301 basic medicine; Luminescence; Genotype; Citric Acid Cycle; Citrate (si)-Synthase; Gene Expression Regulation, Bacterial; Aliivibrio fischeri; Citric Acid; 03 medical and health sciences; Suppression, Genetic; Bacterial Proteins; Mutation; Animals

The Gac/Csr regulatory system is conserved throughout the γ-proteobacteria and controls key pathways in central carbon metabolism, quorum sensing, biofilm formation virulence important plant animal pathogens. Here we show that elevated intracellular citrate levels a Vibrio fischeri aconitase mutant correlate with activation of cascade induction bright luminescence. Spontaneous or directed mutations gene encodes synthase reversed luminescence mutants, eliminated their accumulation expression CsrB. Our data elucidate correlative link between metabolic pathways, they suggest Gac senses blockage at step tricarboxylic acid cycle, either through secondary effect accumulation, responds by modulating flow various functions associated host colonization, including bioluminescence.