Isopropyl-β-D-thiogalactopyranoside (IPTG) is a widely used non-metabolizable inducer of the lac operon in molecular biology. It is a synthetic analog of lactose that can effectively induce gene expression controlled by lac promoter-based systems.
Unlike lactose, IPTG is not hydrolyzed by β-galactosidase, allowing for stable and sustained induction of recombinant protein expression. It binds to the lac repressor (LacI), releasing it from the operator region and enabling transcription of downstream genes.
Due to its reliability and efficiency, IPTG is extensively used in recombinant protein expression, gene regulation studies, and bacterial expression systems, especially in E. coli.
Isopropyl-β-D-thiogalactopyranoside functions as a lac operon inducer.In molecular systems:
This makes IPTG ideal for controlled gene expression systems.
IPTG is widely used to induce protein expression in bacterial systems.Typical applications include:
It is commonly used in studies of gene expression and regulation.Applications include:
IPTG plays a key role in molecular biology techniques.Applications include:
Widely used in engineered biological systems.Applications include:
| Parameter | Recommended Conditions |
| Working Concentration | Typically 0.1–1 mM (optimize as needed) |
| Induction Method | Addition to culture medium |
| Host System | Commonly E. coli expression systems |
| Temperature | 16–37 °C (depending on expression strategy) |
| Assay Format | Liquid culture, agar plates |
Optimal conditions depend on vector, host strain, and target protein.
Researchers working in the following fields may benefit from this compound:
What is IPTG used for?
It is used to induce gene expression in lac operon-based systems, especially in E. coli.
Why is IPTG preferred over lactose?
Because it is non-metabolizable, providing stable and continuous induction.
What concentration of IPTG should be used?
Typically 0.1–1 mM, but optimization is recommended depending on the system.
