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Directed evolution of AraC for improved compatibility of arabinose- and lactose-inducible promoters.

ABSTRACT: Synthetic biological systems often require multiple, independently inducible promoters in order to control the expression levels of several genes; however, cross talk between the promoters limits this ability. Here, we demonstrate the directed evolution of AraC to construct an arabinose-inducible (P(BAD)) system that is more compatible with IPTG (isopropyl-beta-D-1-thiogalactopyranoside) induction of a lactose-inducible (P(lac)) system. The constructed system is 10 times more sensitive to arabinose and tolerates IPTG significantly better than the wild type. Detailed studies indicate that the AraC dimerization domain and C terminus are important for the increased sensitivity of AraC to arabinose.

SUBMITTER: Lee SK

PROVIDER: S-EPMC2074931 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Directed evolution of AraC for improved compatibility of arabinose- and lactose-inducible promoters.

Lee Sung Kuk SK Chou Howard H HH Pfleger Brian F BF Newman Jack D JD Yoshikuni Yasuo Y Keasling Jay D JD

Applied and environmental microbiology 20070720 18

Synthetic biological systems often require multiple, independently inducible promoters in order to control the expression levels of several genes; however, cross talk between the promoters limits this ability. Here, we demonstrate the directed evolution of AraC to construct an arabinose-inducible (P(BAD)) system that is more compatible with IPTG (isopropyl-beta-D-1-thiogalactopyranoside) induction of a lactose-inducible (P(lac)) system. The constructed system is 10 times more sensitive to arabin ...[more]

PMID: 17644634

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