Dataset Information

An Engineered B. subtilis Inducible Promoter System with over 10 000-Fold Dynamic Range.

ABSTRACT: Bacillus subtilis is the leading model Gram-positive bacterium, and a widely used chassis for industrial protein production. However, B. subtilis research is limited by a lack of inducible promoter systems with low leakiness and high dynamic range. Here, we engineer an inducible promoter system based on the T7 RNA Polymerase (T7 RNAP), the lactose repressor LacI, and the chimeric promoter P_T7lac, integrated as a single copy in the B. subtilis genome. In the absence of IPTG, LacI strongly represses T7 RNAP and P_T7lac and minimizes leakiness. Addition of IPTG derepresses P_T7lac and simultaneously induces expression of T7RNAP, which results in very high output expression. Using green fluorescent and β-galactosidase reporter proteins, we estimate that this LacI-T7 system can regulate expression with a dynamic range of over 10 000, by far the largest reported for an inducible B. subtilis promoter system. Furthermore, LacI-T7 responds to similar IPTG concentrations and with similar kinetics as the widely used P_hy-spank IPTG-inducible system, which we show has a dynamic range of at most 300 in a similar genetic context. Due to its superior performance, our LacI-T7 system should have broad applications in fundamental B. subtilis biology studies and biotechnology.

SUBMITTER: Castillo-Hair SM

PROVIDER: S-EPMC9724499 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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An Engineered B. subtilis Inducible Promoter System with over 10 000-Fold Dynamic Range.

Castillo-Hair Sebastian M SM Fujita Masaya M Igoshin Oleg A OA Tabor Jeffrey J JJ

ACS synthetic biology 20190628 7

Bacillus subtilis is the leading model Gram-positive bacterium, and a widely used chassis for industrial protein production. However, B. subtilis research is limited by a lack of inducible promoter systems with low leakiness and high dynamic range. Here, we engineer an inducible promoter system based on the T7 RNA Polymerase (T7 RNAP), the lactose repressor LacI, and the chimeric promoter PT7lac, integrated as a single copy in the B. subtilis genome. In the ...[more]

PMID: 31181163

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An Engineered B. subtilis Inducible Promoter System with over 10 000-Fold Dynamic Range.

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An Engineered <i>B. subtilis</i> Inducible Promoter System with over 10 000-Fold Dynamic Range.

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An Engineered B. subtilis Inducible Promoter System with over 10 000-Fold Dynamic Range.

Publications

An Engineered <i>B. subtilis</i> Inducible Promoter System with over 10 000-Fold Dynamic Range.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

An Engineered B. subtilis Inducible Promoter System with over 10 000-Fold Dynamic Range.

An Engineered <i>B. subtilis</i> Inducible Promoter System with over 10 000-Fold Dynamic Range.