Abstract

Metabolic engineering of yeasts has proven an effective strategy for producing compounds ranging from commodity chemicals to biologics. However, in the case of certain organic acids, there is a toxicity barrier, which prevents commercial production from being viable. To address this problem, we developed a strategy to characterize non-conventional yeasts and used it to search fungal repositories for desirable phenotypes, in our case tolerance to adipic acid, a nylon 6,6 precursor. From publicly accessible yeast collections we selected and screened a collection of 122 strains of yeasts. After finding strains that were tolerant to high concentrations of adipic acid at an industrially relevant pH, suitable antibiotic markers were found and whole genome sequencing and annotation was performed to enable future metabolic engineering efforts in these strains. Annotated strains were examined for evidence of gene expansion in families commonly associated with organic acid tolerance and candidate genes were identified for further research