In Saccharomyces cerevisiae, recombinant protein secretion can be plagued with low titers.  While different genetic or bioprocessing modifications may improve titer for a particular protein, these strategies are not generalizable to other proteins.  This implies there are several possible bottlenecks in the secretory pathway, and producing different proteins may be constrained in different ways.  In this study, we use a system level analysis (transcriptomics, metabolomics, and physiological responses) to characterize S. cerevisiae secreting different size proteins, while perturbing secretory homeostasis through HAC1.  Prominent changes in redox stress and NADPH consumption lead us to develop a redox model for disulfide bond formation in the ER.  By accounting for electron affinities between redox partners, we could predict futile cycles that produce ROS and could propose hypotheses to mitigate the futile cycle.  This work identifies counterintuitive interventions (slowing disulfide bond formation or protein synthesis) that may improve recombinant protein production more generally.

Balancing act in the endoplasmic reticulum: Relative folding and disulfide bond formation rates are key to secretory homeostasis

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.