Enhancing stress resistance and production phenotypes through transcriptome engineering.

摘要: As Saccharomyces cerevisiae is engineered further as a microbial factory for industrially relevant but potentially cytotoxic molecules such ethanol, issues of cell viability arise that threaten to place biological limit on output capacity and/or the use less refined production conditions. Evidence suggests one naturally evolved mode survival in deleterious environments involves complex, multigenic interplay between disparate stress response and homeostasis mechanisms. Rational engineering resistance would require systems-level understanding cellular behavior is, general, not yet available. To circumvent this limitation, we have developed phenotype discovery approach termed global transcription machinery (gTME) allows generation selection nonphysiological traits. We alter gene expression genome-wide scale by selecting dominant mutations randomly mutagenized general factor. The encoding mutated factor resides plasmid strain carrying unaltered chromosomal allele. Thus, although may destroy essential function plasmid-borne variant, alteration transcriptome with minimal perturbation normal processes possible via presence native genomic Achieving interest construction diversity evaluation yeast libraries harboring random sequence variants chosen subsequent validation mutant strains. describe rationale procedures associated each step context generating strains possessing enhanced ethanol tolerance.