2-NITROPHENYL-BETA-D-GLUCOPYRANOSIDE CAS:2816-24-2

Enzyme substrate: ONPG is commonly used as a substrate for beta-galactosidase, an enzyme that hydrolyzes ONPG to produce a yellow-colored compound (o-nitrophenol) that can be easily detected spectrophotometrically. This enzymatic reaction can be used to measure the activity of beta-galactosidase, making ONPG a valuable tool in enzymology studies.

Molecular biology assays: ONPG is used as a substrate in various molecular biology assays, particularly in beta-galactosidase reporter gene assays. In these assays, an ONPG-based substrate is used to measure the activity of the reporter gene, which is typically regulated by a particular promoter sequence of interest. The beta-galactosidase activity, indicated by the color change produced upon ONPG hydrolysis, provides valuable information about the promoter activity.

Gene expression analysis: ONPG is also used in the analysis of gene expression. By linking the promoter sequence of interest to the beta-galactosidase gene, researchers can measure the beta-galactosidase activity using ONPG as a substrate. The level of beta-galactosidase activity is reflective of the strength and activity of the promoter, allowing for the assessment of gene expression levels.

Diagnostic applications: ONPG can be used in diagnostic applications, particularly in the detection of pathogenic microorganisms. Various bacteria, such as Escherichia coli and certain species of Shigella and Salmonella, produce beta-galactosidase which can cleave ONPG. This hydrolysis reaction produces a visible color change, which can be used to determine the presence of these bacteria in clinical samples.