Academic Journal

Carbon dioxide fixation via production of succinic acid from glycerol in engineered Saccharomyces cerevisiae

التفاصيل البيبلوغرافية
العنوان: Carbon dioxide fixation via production of succinic acid from glycerol in engineered Saccharomyces cerevisiae
المؤلفون: Zahabiya Malubhoy, Frederico Mendonça Bahia, Sophie Claire de Valk, Erik de Hulster, Toni Rendulić, Juan Paulo Ragas Ortiz, Joeline Xiberras, Mathias Klein, Robert Mans, Elke Nevoigt
المصدر: Microbial Cell Factories, Vol 21, Iss 1, Pp 1-15 (2022)
بيانات النشر: BMC, 2022.
سنة النشر: 2022
المجموعة: LCC:Microbiology
مصطلحات موضوعية: Succinic acid, Glycerol, Yeast, Metabolic engineering, CO2 fixing, Saccharomyces cerevisiae, Microbiology, QR1-502
الوصف: Abstract Background The microbial production of succinic acid (SA) from renewable carbon sources via the reverse TCA (rTCA) pathway is a process potentially accompanied by net-fixation of carbon dioxide (CO2). Among reduced carbon sources, glycerol is particularly attractive since it allows a nearly twofold higher CO2-fixation yield compared to sugars. Recently, we described an engineered Saccharomyces cerevisiae strain which allowed SA production in synthetic glycerol medium with a maximum yield of 0.23 Cmol Cmol−1. The results of that previous study suggested that the glyoxylate cycle considerably contributed to SA accumulation in the respective strain. The current study aimed at improving the flux into the rTCA pathway accompanied by a higher CO2-fixation and SA yield. Results By changing the design of the expression cassettes for the rTCA pathway, overexpressing PYC2, and adding CaCO3 to the batch fermentations, an SA yield on glycerol of 0.63 Cmol Cmol−1 was achieved (i.e. 47.1% of the theoretical maximum). The modifications in this 2nd-generation SA producer improved the maximum biomass-specific glycerol consumption rate by a factor of nearly four compared to the isogenic baseline strain solely equipped with the dihydroxyacetone (DHA) pathway for glycerol catabolism. The data also suggest that the glyoxylate cycle did not contribute to the SA production in the new strain. Cultivation conditions which directly or indirectly increased the concentration of bicarbonate, led to an accumulation of malate in addition to the predominant product SA (ca. 0.1 Cmol Cmol−1 at the time point when SA yield was highest). Off-gas analysis in controlled bioreactors with CO2-enriched gas-phase indicated that CO2 was fixed during the SA production phase. Conclusions The data strongly suggest that a major part of dicarboxylic acids in our 2nd-generation SA-producer was formed via the rTCA pathway enabling a net fixation of CO2. The greatly increased capacity of the rTCA pathway obviously allowed successful competition with other pathways for the common precursor pyruvate. The overexpression of PYC2 and the increased availability of bicarbonate, the co-substrate for the PYC reaction, further strengthened this capacity. The achievements are encouraging to invest in future efforts establishing a process for SA production from (crude) glycerol and CO2.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1475-2859
Relation: https://doaj.org/toc/1475-2859
DOI: 10.1186/s12934-022-01817-1
URL الوصول: https://doaj.org/article/ef8bb4c8c8a548dea7c793046cedeb49
رقم الانضمام: edsdoj.f8bb4c8c8a548dea7c793046cedeb49
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:14752859
DOI:10.1186/s12934-022-01817-1