ONPG B-Galactosidase Assay Kit is an optimized, stable and convenient tool to quickly measure the levels of active β-galactosidase expressed in cells transfected with plasmids expressing Lac Z.
Lac Z is often used reporter gene in experiments transfection because the β-galactosidase is very resistant to proteolytic degradation and its activity is easily measured. β-galactosidase performs the hydrolysis of orthonitrophenyl-β-D-galactopyranoside (ONPG) to the ortho-nitrophenol (ONP). This ONP produces a bright yellow colour that is detected at an absorbance of 420 nm. The concentration of β-galactosidase is proportional to colour produced.
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