Project description:We used RNA-seq to investigate the effects of single transcription factor knockouts on growth of E. coli BW25113 in fed-batch cultures at multiple timepoints. Cells were grown in an ambr automated bioreactor and maintained at 30 degrees and pH 6.5 in Medium C.
Project description:High titer, rates, yields (TRY) and scalability are challenging metrics to achieve due to trade-offs between carbon use for growth and production. To achieve these metrics, we took the minimal cut set (MCS) approach that predicts metabolic reactions for elimination to couple metabolite production strongly with growth. We computed MCS solution-sets for a non-native product indigoidine, a sustainable pigment, in Pseudomonas putida KT2440, an emerging industrial microbe. From 63 computed solution-sets, our -omics guided process identified one experimentally feasible solution requiring 14 simultaneous reaction interventions. Using multiplex-CRISPRi, this is the first experimental implementation of a 14-gene MCS-based solution that shifted production from stationary to exponential phase. We achieved 25.6 g/L, 0.22 g/l/h, and ~50% maximum theoretical yield (0.33 g indigoidine/g glucose) TRY respectively. These phenotypes were maintained from batch to fed-batch mode, and across scales (100-ml shake flasks, 250-ml ambr® and 2-L bioreactors).
Project description:This study aims to investigate the DNA methylation patterns at transcription factor binding regions and their evolutionary conservation with respect to binding activity divergence. We combined newly generated bisulfite-sequencing experiments in livers of five mammals (human, macaque, mouse, rat and dog) and matched publicly available ChIP-sequencing data for five transcription factors (CEBPA, HNF4a, CTCF, ONECUT1 and FOXA1). To study the chromatin contexts of TF binding subjected to distinct evolutionary pressures, we integrated publicly available active promoter, active enhancer and primed enhancer calls determined by profiling genome wide patterns of H3K27ac, H3K4me3 and H3K4me1.