Please note that we have stopped the regular imports of Gene Expression Omnibus (GEO) data into ArrayExpress. This may not be the latest version of this experiment.
E-GEOD-4872 - Response of Lactococcus lactis to isoleucine starvation
Submitted on 18 May 2006, released on 25 June 2010, last updated on 27 March 2012
For the first time in Lactococcus lactis, amino acid starvation response was characterized. The natural imposition of isoleucine starvation, by its consumption during growth, associated to transcript profiling, allowed defining exhaustively this stress stimulon. It consisted of a general induction of nitrogen metabolism (amino acid biosynthesis and transport, proteolytic system and proteases), a strong repression of genes encoding major physiological activities (translation, transcription, carbon metabolism, purine and pyrimidine biosynthesis and fatty acid metabolism) and the induction of unexpected cross responses to acid, osmotic and oxidative stresses. Keywords: stress response, time course Isoleucine starvation was imposed by the consumption of this amino acid during the growth of Lactococcus lactis IL1403 on ILV0.1 medium (CDM with ten-fold reduced concentrations of isoleucine, leucine and valine) and under controlled conditions (30 °C, pH 6.6, nitrogen atmosphere). Cell samples were harvested in exponential phase and after 30 min, 1.7 h and 3.5 h of isoleucine starvation. Total RNA was extracted from these samples and radiolabelled cDNA were prepared and hybridized on nylon arrays. 2053 amplicons specific of Lactococcus lactis IL1403 genes were spotted twice on the array. The 4 time-points were analyzed simultaneously and 3 independent repetitions were performed.
transcription profiling by array
Muriel Cocaign-Bousquet <firstname.lastname@example.org>, Emma Redon, Pascal Loubiere
Growth rate regulated genes and their wide involvement in the Lactococcus lactis stress responses. Dressaire C, Redon E, Milhem H, Besse P, Loubière P, Cocaign-Bousquet M.