Page 4 - C. Biotechnology and molecular imaging

[C. Biotechnology and molecular imaging-4]

Auto-inducible, dynamic, and antibiotic-free expression

system in Escherichia coli for the production of farnesol

Mst Fayzunnesa¹, Seon-won Kim¹˙*

¹Division of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828,

Republic of Korea

Engineered E.coli MG1655 strain overexpressing heterologous MVA pathway genes or along with native MEP,
pathway produces IPP and DMAPP building blocks for FPP synthesis catalyzed by FPP synthase (IspA). Subsequently,

FPP could then be depyrophosphorylated to form farnesol via NudJ, an E.coli native phosphatase suspected to

dephosphorylate IPP and DMAPP to isoprenoid alcohols. To establish an auto-inducible and dynamic system IspA,
idi, and MVA pathway genes were overexpressed under the control of inducer-free promoters PgadE and PrstA
instead of inducer dependent promoter Plac and Ptrc successfully producing 384 mg/L total farnesol and farnesol

derivatives (farnesal and farnesyl acetate) for 48 hours. The development of sustainable large scale farnesol
production requires an antibiotic-free system in order to avoid additional downstream purification and separation

steps while decreasing overall production cost. The antibiotic-free strain was able to maintain the production
plasmids without antibiotics, achieving 1.4g/L of farnesol and farnesol derivatives in a fed-batch culture system or

1.3fold better than with antibiotics.

This work was supported by the grant from the Next-Generation BioGreen 21 Program (SSAC grant#: PJ01326501),

RDA, Korea.