Project description:Populations of engineered metabolite-producing microorganisms are prone to evolutionary production declines during industrial-scale cultivations. In this study, we develop a synthetic product addiction system in E coli that addicts mevalonic acid production cells to mevalonic acid. Through experimentally simuluated long-term fermentation, we investigate how product-addicted organisms remain stable and avoid formation of genetic subpopulations of fit, non-producing cells.
Project description:We have integrated nucleotide resolution genome-scale measurements of the transcriptome and translatome of the Streptomyces coelicolor A3(2), the model antibiotic-producing actinomycete. Our systematic study determined 3,473 transcription start sites, leading to discovery of a high proportion (~21%) of leaderless mRNAs and 230 non-coding RNAs; this enabled deduction of promoter architecture on a genome-scale. Ribosome profiling analysis revealed that the translation efficiency was negatively correlated for secondary metabolic genes. These results provide novel fundamental insights into translational regulation of secondary metabolism that enables rational synthetic biology approaches to awaken such âsilentâ secondary metabolic pathways. Profiles of primary transcripts, whole transcripts, and ribosome protected fragments (RPFs) of Streptomyces coelicolor were generated by deep sequencing using Illumina Miseq.
