Understanding the intracellular effects of yeast extract on the enhancement of Fc-fusion protein production in Chinese hamster ovary cell culture

Abstract

Yeast extract (YE), as a non-animal source additive for mammalian cell culture medium, has been widely used for manufacturing of therapeutic proteins. In the present study, one particular YE was found to have significantly improved the specific productivity (q p) of Fc-fusion protein in recombinant Chinese hamster ovary (rCHO) cell culture. In order to elucidate the intracellular effects of YE on protein productivity, steps of the target protein synthesis process were investigated to unveil their variations caused by YE addition. Stepwise analysis on Fc-fusion protein synthesis process showed that YE enhanced Fc-fusion protein gene transcription with cell cycle arrest at G1 phase; mammalian target of rapamycin (mTOR) signaling pathway was activated to enhance the translation of Fc-fusion protein, and the block in post-translational steps of Fc-fusion protein was alleviated by YE addition as well. Our results revealed the responses of multiple protein production steps to the addition of YE and provided a practical guidance for the separation and application of active compounds from hydrolysates.

Machine learning modeling of the effects of media formulated with various yeast extracts on heterologous protein production in Escherichia coli

“…Yeast extract is a complex raw material usually produced from baker's or brewer's yeast through autolysis or chemical digestion (Bekatorou et al, 2006; Ferreira et al, 2010). It is also used as supplemental material in serum‐free media for mammalian cell culture and human immunoglobulin production (Hu et al, 2015; Mosser et al, 2013). The composition varies among lots and brands because of its complex substrates, uncontrolled fermentation conditions during yeast cultivation, and variation of downstream processes during manufacturing (Christ & Blank, 2019).…”

Increased MSX level improves biological productivity and production stability in multiple recombinant GS CHO cell lines

“…Q p may be affected by a variety of factors including the primary amino acid sequence of the expressed protein , the global cellular gene expression regulation for vesicle trafficking, endocytosis and cytoskeletal elements , the activities of the mammalian target of rapamycin pathway and global protein translation , the function activity of mitochondria as well as the extracellular and intracellular redox environment . Modulation of intracellular microRNA (miR) levels has been shown to successfully increase q p by regulating cell cycle with miR‐7 , protein synthesis, secretion and transport with miR‐557 and miR‐1287 and mitochondrial genome‐encoded small RNA (mitosRNA‐1978) , and by balancing unfolded protein response (UPR) program with miR‐1287 .…”

“…Application of tyrosine‐, histidine‐, or glutamine‐containing dipeptides, substitution of glutamine with alpha‐ketoglutarate (alpha‐KG), or altering the glutamine levels in media have been reported to lower lactate and ammonia production, thus providing better pH maintenance, improved q p , and overall process yield . Yeast extracts produced a beneficial effect on q p by maintaining the mammalian target of rapamycin pathway activity and enhancing protein translation .…”

Recent advances in in-vitro meat production – a review

“…Various plant protein hydrolysates were used for the cell culture such as whey protein isolates prepared by using alcalase and protamex reported to induce proliferation and differentiation of MC3T3-E1 osteoblasts (Jo et al, 2020 b). Similarly, yeast extracts were observed to induce cell growth and monoclonal antibody production in Chinese hamster ovary (CHO) cells (Hu et al, 2017). The application of algal extract was observed to substitute glucose and amino acids in basal cell media used for growing C2C12 mouse myoblasts (Okamoto et al, 2020).…”