Effect of NaCl concentration on the transcriptional network of E. coli in glucose minimal medium with glycine betaine. Escherichia coli K-12

The growth rate of E. coli decrease continuously with NaCl concentration, however the pattern for metabolic efficiency as measured by optical density is corralated to a change in pattern in transcription data and proteomics.The analysis of the data suggest that between 4.5 and 5% NaCl, the metabolism switched from aerobic to fermentative pathways. The response to osmotic stress is similar to a response to oxidative stress. An example how a stagewise metabolic answer may be the result of continuously increasing stress. Overall design: Study of the pattern of gene expression as a function of NaCl concentrations (2%, 3.5% -2 replicates-, 4.5%, 5%, 5.5%). To compare the different conditions, cDNA was normalised to genomic DNA, gDNA.