Choi, Sun Young Wang, Jin-Young Kwak, Ho Seok Lee, Sun-Mi Um, Youngsoon Kim, Yunje Sim, Sang Jun Choi, Jong-il Woo, Han Min 2024-01-20T01:03:40Z 2024-01-20T01:03:40Z 2021-09-05 2017-07 2161-5063 https://pubs.kist.re.kr/handle/201004/122580 The push-and-pull strategy for metabolic engineering was successfully demonstrated in Synechococcus elongatus PCC 7942, a model photosynthetic bacterium, to produce squalene from CO2. Squalene synthase (SQS) was fused to either a key enzyme (farnesyl diphosphate synthase) of the methylerythritol phosphate pathway or the beta-subunit of phycocyanin (CpcB1). Engineered cyanobacteria with expression of a fusion CpcB1-SQS protein showed a squalene production level (7.16 +/- 0.05 mg/L/OD730) that was increased by 1.8-fold compared to that of the control strain expressing SQS alone. To increase squalene production further, the gene dosage for CpcB1.SQS protein expression was increased and the fusion protein was expressed under a strong promoter, yielding 11.98 +/- 0.49 mg/L/OD730 of squalene, representing a 3.1-fold increase compared to the control. Subsequently, the best squalene producer was cultivated in a scalable photobioreactor (6 L) with light optimization, which produced 7.08 +/- 0.5 mg/L/OD730 squalene (equivalent to 79.2 mg per g dry cell weight). Further optimization for photobioprocessing and strain development will promote the construction of a solar-to-chemical platform. English American Chemical Society Improvement of Squalene Production from CO2 in Synechococcus elongatus PCC 7942 by Metabolic Engineering and Scalable Production in a Photobioreactor Article 10.1021/acssynbio.7b00083 1 ACS Synthetic Biology, v.6, no.7, pp.1289 - 1295 ACS Synthetic Biology 6 7 1289 1295 N scie scopus 000406356100020 2-s2.0-85025175891 Biochemical Research Methods Biochemistry & Molecular Biology Article ESCHERICHIA-COLI CYANOBACTERIA BIOSYNTHESIS EXPRESSION CONVERSION PATHWAY AMORPHA-4,11-DIENE SYNTHASE BIOLOGY PROTEIN Synechococcus elongatus PCC 7942 protein engineering metabolic engineering squalene CO2 conversion scalable production