Nitrophenyl β-D-galactopyranoside, ONPG
 
Catalog Number: ASC-1022
CAS Number: 369-07-3
MW: 301.2 g/mol
MF: C12H15NO8
 
The chromogenic substrate Nitrophenyl β-D-galactopyranoside is utilized in quantitative investigations and the kinetics of the beta-galactosidase enzyme.
In molecular biology, it is employed in tests to measure the activity of β-galactosidase reporter gene constructs. This test is frequently used in diagnostics to identify Enterobacteriaceae family lactose-fermenting bacteria.
Two enzymes are required for lactose utilization: β-galactosidase, which breaks down lactose into galactose and glucose, and β-galactoside permease, which catalyzes the transport of lactose into the cell. Without specificity towards lactose, β-Galactosidase can function on basic galactosides, such as the ONPG substrate. Galactose and o-nitrophenol, a yellow chromogenic molecule, are released upon ONPG hydrolysis. ONPG, does not require an induced or constitutive permease enzyme to enter the cell.
 
For Laboratory Use Only, Not For Human or Animal Usage.