Overcoming the metabolic burden of protein secretion in Schizosaccharomyces pombe – A quantitative approach using 13C-based metabolic flux analysis

Comparative Proteome Analysis in Schizosaccharomyces pombe Identifies Metabolic Targets to Improve Protein Production and Secretion

“…For S. pombe strains NW8 and NW9 a reduction of glycolytic and TCA cycle fluxes has been recently demonstrated and was attributed to an increased precursor demand and increasing efficiency of substrate utilization because of high level protein production (13). One major difference was observed between the previous study and the present findings: the abundance decrease of glucose-6-phosphate dehydrogenase and fructose-1,6-bisphosphatase as well as the increase in glucose-6-phosphate isomerase here suggest a switch in the split ratio between PPP and glycolysis toward the latter, whereas elevated protein secretion resulted in an increase of PPP fluxes in the former study (13). This difference might however be also due the domination of regulation effects on the metabolite level, e.g.…”

“…Thus, the metabolic burden caused by the increased maltase secretion clearly observable from the proteome data was not reflected in the extracellular metabolites. These findings are apparently in contrast to a previous study of maltase overexpression (13). However, in the previous study, respiratory growth conditions were applied, which results in highly efficient substrate utilization.…”

“…Strain Construction-Construction of S. pombe strains NW8 and NW9 has been described before (13). For the construction of strain NW10, the fission yeast gene agl1 (16) was amplified from genomic fission yeast DNA by PCR with flanking primers that introduce restriction sites for NdeI (5Ј) and BamHI (3Ј), respectively.…”

“…Regarding lipid metabolism, we observed a reduction of protein abundance of both glycerol-3-phosphate dehydrogenases (Gld1p and Gut2p). It has previously been shown that deletion of these proteins in the yeast Yarrowia lipolytica leads to a threefold increase in lipid production and accumulation (36), and that high-level protein secretion in S. pombe correlates with increased cellular lipid content (13). In addition, the protein Lsd90, which plays a role in the metabolism of very long chain fatty acids (37), and a predicted 3-hydroxyacyl-CoA dehydrogenase (SPAC4H3.08), involved in lipid degradation, were significantly decreased in abundance in the NW10 strain.…”

“…In a recent study, we investigated the effects of increased maltase secretion on the central carbon metabolism of S. pombe using 13 C-assisted metabolic flux analysis (13). In this study, we were interested in the system wide proteomic response of S. pombe cells to the increased level of protein secretion.…”