Related Experiment Video
Updated: Nov 19, 2025
10:09
Inducible T7 RNA Polymerase-mediated Multigene Expression System, pMGX
Published on: June 27, 2017
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Expression of Cloned Genes in E. coli Using IPTG-Inducible Promoters
Cold Spring Harbor Protocols
|February 2, 2021
Abstract:
Many Escherichia coli expression vectors make use of the lac operon. In general, the lac operator (lacO) is located downstream from the promoter of the target gene, so that binding of the lac repressor blocks transcription initiation until lactose or the isopropyl-β-d-thiogalactopyranoside (IPTG) analog is added. The protocol given here is intended for use with IPTG-inducible vectors. l-Arabinose-inducible systems derived from the ara operon offer an alternative to expression systems based on the lac operon; guidance for their use is also provided.
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