IPTG is a common abbreviation for Isopropyl β-D-1-thiogalactopyranoside, a molecular biology reagent. It has a molecular weight of 238.3.

This compound is used as a molecular mimic of allolactose, a lactose metabolite that triggers transcription of the lac operon. Unlike allolactose, the sulfur (S) atom creates a chemical bond which is non-hydrolyziable by the cell, preventing the cell from "eating up" the inductant.

Many regulatory elements of the lac operon are used in inducible recombinant protein systems; IPTG is an effective inducer in the concentration range of 100 micromolar to 1.5 millimolar.

External links

• IPTG's property from Acros

Carbohydrates

Isopropyl-β-D-thiogalactopyranosid