what is the role of X gal in the Beta galactosidase assaySol

what is the role of X gal in the Beta galactosidase assay?

Solution

X gal is a blue coloured product. The role of X gal in beta galactosidase assay is that it is used as a visual indicator to show whether a particular cell can express functional enzyme beta galactosidase in bkue or white screening technique. Cells are made to grow in a plate which contains X gal and if active beta galactosidase are found, blue colonies are formed.