5-Bromo-4-chloro-3-indolyl β-D-galactopyranoside is most commonly known as X-Gal. X-gal is a histochemical substrate for β-galactosidase which cleaves X-Gal to yield an insoluble blue precipitate.
X-Gal is a mainstay in molecular biology cloning applications in which it is used to detect the activity of β-galactosidase. X-Gal is used to detect the insertion of foreign DNA into the lacZ region of a plasmid DNA. Insertion of DNA into the lacZ region results in the loss of β-galactosidase activity.
X-gal is used to indicate whether a cell expresses the β-glactosidase enzyme, which is encoded by the lacZ gene, in a technique called blue white screening. Bacterial cells that retain active β-galactosidase will result in characteristic blue colonies. Successful disruption of the lacZα gene disrupts the α-complementation of the β-galactosidase gene and the precipitate does not form, resulting in white colonies.
Additional Information
| Synonyms | BCIG |
|---|---|
| Product # | X-1015 |
| CAS # | 7240-90-6 |
| Chemical Name | 5-Bromo-4-Chloro-3-Indolyl-B-D-Galactopyranoside |
| Formula | C14H15BrClNO6 |
| MW | 408.61 |
| Appearance | White Powder |
| Purity | 99% (TLC) |
| Solubility | Soluble 2% in DMF |
| Melting Point | 236-238 °C |
| Storage Temp | -20°C |
| Use | A chromogenic histochemical substrate for β-galactosidase used to detect DNA insertions into the lacZ region of plasmid DNA |
Additional Information
| MDL Number | MFCD00005666 |
|---|---|
| ChemACX | X1009969-1 |
| InChI | InChI=1S/C14H15BrClNO6/c15-5-1-2-6-9(10(5)16)7(3-17-6)22-14-13(21)12(20)11(19)8(4-18)23-14/h1-3,8,11-14,17-21H,4H2/t8-,11+,12+,13-,14-/m1/s1 |
| SMILES | c1cc(c(c2c1[nH]cc2O[C@H]3[C@@H]([C@H]([C@H]([C@H](O3)CO)O)O)O)Cl)Br |
