Hyperosmolarity adversely impacts heterologous secretory protein synthesis by Yarrowia lipolytica

ABSTRACT: In this research we were interested in answering a question whether subjecting Y. lipolytica strain overproducing recombinant secretory protein (rs-Prot) to a specific, pre-optimized stress factor may enhance synthesis of the target macromolecule. Increased osmolarity (3 Osm/kg) was the primary stress factor studied here, implemented alone or in combination with decreased temperature (20C), known to promote synthesis of rs-Prots. The treatments were executed in batch bioreactor cultures, and the cellular reaction was studied in terms of the culture progression, gene expression and global proteomic profiles, to get insight into molecular bases underlying awaken reaction. First of all, we observed that hyperosmolarity executed by high sorbitol concentration does not enhance synthesis of the rs-Prot, but increases its transcription. Expectedly, hyperosmolarity induced synthesis of polyols, at the expense of citric acid and growth, which was severely limited. A number of stress-related genes were upregulated, including several HSPs, AKRs, as observed at transcriptomics and proteomics level. Interestingly, the accompanying concerted downregulation of central carbon metabolism, incl. glycolysis, TCA and fatty acid synthesis, highlighted redirection of carbon fluxes. Elevated abundance of HSPs and osmolytes did not outbalance severe limitation of protein synthesis, marked by orchestrated downregulation of translation (EF-gamma; a number of aa-tRNA synthetases), amino acids biosynthesis and ribosome biogenesis in response to hyperosmolarity. Altogether we ultimately settled that increased osmolarity is not beneficial for rs-Prot synthesis in Y. lipolytica, even though some elements of the response could assist this process. Insight into global changes in the yeast proteome under the treatments is provided.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Yarrowia Lipolytica (ncbitaxon:4952)

SUBMITTER: Ewelina Celinska  

PROVIDER: MSV000088228 | MassIVE | Wed Oct 13 04:50:00 BST 2021

SECONDARY ACCESSION(S): PXD029106

REPOSITORIES: MassIVE