Description: X-Gal is the abbreviation for 5-Bromo-4-chloro-3-indolyl β-D-galactopyranoside; less commonly the abbreviation BCIG is also used. X-Gal is enzymatically hydrolysed by β-galactosidase to yield galactose and 5-bromo-4-chloro-3-hydroxyindole. The soluble, colourless, indole hydrolysis product is subsequently transformed into an insoluble blue compound, 5,5’-dibromo-4,4’-dichloro indigo, via a dimerisation and oxidation sequence. X-Gal is frequently used in molecular biology applications to indicate the activity of β-galactosidase, an enzyme encoded by the lacZ gene, a classical reporter gene. In gene cloning, a X-Gal blue/white colony screening assay can be used to differentiate recombinant colonies which stain white from non-recombinant ones which stain blue.
Chemical formula: C14H15BrClNO6
CAS number: 7240-90-6
Soluble in: DMSO and DMF
Storage: -20 ºC