Modular optimization of multi-gene pathways for fatty acids production in E. coli.
Microbial fatty acid-derived fuels have emerged as promising alternatives to petroleum-based transportation fuels. Here we report a modular engineering approach that systematically removed metabolic pathway bottlenecks and led to significant titre improvements in a multi-gene fatty acid metabolic pathway. On the basis of central pathway architecture, E. coli fatty acid biosynthesis was re-cast into three modules: the upstream acetyl coenzyme A formation module; the intermediary acetyl-CoA activation module; and the downstream fatty acid synthase module. Combinatorial optimization of transcriptional levels of these three modules led to the identification of conditions that balance the supply of acetyl-CoA and consumption of malonyl-CoA/ACP. Refining protein translation efficiency by customizing ribosome binding sites for both the upstream acetyl coenzyme A formation and fatty acid synthase modules enabled further production improvement. Fed-batch cultivation of the engineered strain resulted in a final fatty acid production of 8.6 g l(-1). The modular engineering strategies demonstrate a generalized approach to engineering cell factories for valuable metabolites production.
Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180, USA.
Peng
P
Xu
Qin
Q
Gu
Wenya
W
Wang
Lynn
L
Wong
Adam G W
AG
Bower
Cynthia H
CH
Collins
Mattheos A G
MA
Koffas
D001483:Base Sequence; D061249:Batch Cell Culture Techniques; D001665:Binding Sites; D019149:Bioreactors / Q000382:microbiology; D053898:Biosynthetic Pathways / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D004952:Esters / Q000378:metabolism; D005227:Fatty Acids / Q000096:biosynthesis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D018628:Gene Dosage; D005798:Genes, Bacterial / Q000235:genetics*; D060847:Metabolic Engineering; D008969:Molecular Sequence Data; D010100:Oxygen / Q000378:metabolism; D014176:Protein Biosynthesis / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic
D004952:Esters; D005227:Fatty Acids; D010100:Oxygen