Thermo Scientific X-Gal (5-bromo-4-chloro-3-indolyl-β-D-pyran Galactosidase) is an inert chromogenic substrate of β-galactosidase, which hydrolyzes X-Gal to produce colorless galactose and 4-chloro-3-bromo-indigo, forming a dark blue precipitate. Using IPTG to induce the lacZ gene can lead to X-Gal hydrolysis and blue colonies Formation (SeeSupporting Data).

Applications

• Blue-white colony screening to distinguish recombinant (white) from non-recombinant (blue) colonies (see Reference Literature 1)
•Visualization of β-galactosidase reporter gene expression in transfected eukaryotic cells
•Detection of β-galactosidase activity in immunological and histochemical procedures

NOTE
•It is recommended to prepare a 20 mg/mL stock solution of X-Gal in dimethylformamide (DMF) or dimethyl sulfoxide (DMSO). DMF can dissolve some plastic materials. Therefore avoid adding solutions containing dimethylformamide directly into plastic Petri dishes.
•DMF is toxic. Allow the X-Gal solution containing dimethylformamide to dry completely before spreading bacteria on agar plates.

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X-Gal< br>Ready-to-use X-Gal solution