Properties and Applications:
X-a-gal (5-Bromo-4-Chloro-3-indolyl-a-D-galactopyranoside) is a chromogenic substance used to demonstrating a-galactosidase activity. Thus yeast S. cerevisiae which are positive for this enzyme produce blue colonies when grown in the presence of X-a-gal. Used in yeast two-hybrid screens.
X-a-gal should be dissolved in DMF at a concentration of 2mg/ml for premade plates or 20mg/ml for indicator plates.

Analytical Specifications:
Recommended storage condition: frozen at -20° C for 6 month
Molecular weight: 408.6
Melting point: 232-234° C