Expression profile of E. coli in response to exogenous addition of isopentenol

Exogenous isopentenol was added to a culture of E. coli and the RNA expression response was measured using Nimblegen arrays. Genes highly upregulated were then subsequently overexpressed to improve the tolerance to isopentenol toxicity. In addition a subset of genes that improved the tolerance were also overexpressed in a producing strain, leading to improved production over the empty vector control. This work is described in Foo et al, Improving microbial bio-gasoline production in E. coli using tolerance engineering (in preparation) Six independent biological replicates were grown in M9 medium. 0.2% v/v isopentenol was added to 3 cultures while 3 cultures received no treatment, and 2.5 hr later total RNA was extracted. One sample from each culture was hybridized.