Evaluation of Long-Term Fermentation Performance with Engineered Saccharomyces cerevisiae Strains

The performance of a microbial fermentation on an industrial scale is subjected to the robustness of the strain. Such strains are genetically engineered to optimize the production of desired compounds in minimal time, but they often fail to maintain high productivity levels for many generations, hindering their effective application in industrial conditions. This study focused on assessing the impact of genomic instability in yeasts that were engineered to produce a fluorescent output by incorporating a reporter gene at one or more genomic locations. The fermentation performance of these strains was evaluated over 100 generations in a sequential batch set-up. In order to bridge the gap between strain engineering and industrial implementation, we proposed the use of novel, host-specific parameters to standardize the strain robustness and evaluate potential improvements. It was observed that yeasts carrying multiple copies of the reporter gene exhibited a more pronounced decrease in output, and the genomic integration site significantly influenced the production. By leveraging these new, host-specific parameters, it becomes possible to anticipate strain behavior prior to incurring substantial costs associated with large-scale production. This approach enhances the economic viability of novel microbial fermentation processes and narrows the divide between laboratory findings and industrial applications.

Automated summary

This study assessed the impact of genomic instability on the fermentation performance of engineered yeasts, and proposed the use of novel host-specific parameters to standardize strain robustness and evaluate potential improvements. By leveraging these parameters, it becomes possible to predict strain behavior prior to large-scale production, enhancing the economic viability of microbial fermentation processes and bridging the gap between laboratory findings and industrial applications.