Skip to Content
Merck
All Photos(4)

Key Documents

N1127

Sigma-Aldrich

2-Nitrophenyl β-D-galactopyranoside

≥98% (enzymatic)

Synonym(s):

ONPG , o-Nitrophenyl β-D-galactopyranoside, ONPG

Sign Into View Organizational & Contract Pricing


About This Item

Empirical Formula (Hill Notation):
C12H15NO8
CAS Number:
Molecular Weight:
301.25
Beilstein:
92207
EC Number:
MDL number:
UNSPSC Code:
12352200
PubChem Substance ID:
NACRES:
NA.52

grade

for molecular biology

Quality Level

Assay

≥98% (enzymatic)

form

powder

storage temp.

−20°C

SMILES string

OC[C@H]1O[C@@H](Oc2ccccc2[N+]([O-])=O)[C@H](O)[C@@H](O)[C@H]1O

InChI

1S/C12H15NO8/c14-5-8-9(15)10(16)11(17)12(21-8)20-7-4-2-1-3-6(7)13(18)19/h1-4,8-12,14-17H,5H2/t8-,9+,10+,11-,12-/m1/s1

InChI key

KUWPCJHYPSUOFW-YBXAARCKSA-N

Looking for similar products? Visit Product Comparison Guide

General description

ONPG (2-Nitrophenyl β-D-galactopyranoside) is a colorimetric substrate for β-galactosidase.

Application

2-Nitrophenyl β-D-galactopyranoside is an enzyme substrate used to detect lacZ activity and hence the presence of β-galactosidase.

Biochem/physiol Actions

β-galactosidase, breaks down lactose into galactose and glucose. β-Galactosidase is not lactose specific and can act on simple galactosides. 2-Nitrophenyl β-D-galactopyranoside hydrolysis results in the release of galactose and a yellow chromogenic compound. The test substrate does not depend on an induced or constitutive permease enzyme to enter the cell, therefore reactions are rapid and occur within a 24-hour period.

Principle

β-galactosidase, breaks down lactose into galactose and glucose. β-Galactosidase is not lactose specific and can act on simple galactosides. 2-Nitrophenyl β-D-galactopyranoside hydrolysis results in the release of galactose and a yellow chromogenic compound. The test substrate does not depend on an induced or constitutive permease enzyme to enter the cell, therefore reactions are rapid and occur within a 24-hour period.

Reconstitution

A stock solution can be prepared in molecular biology grade water at a concentration of 3 mg/ml. Alternatively, a stock solution of approximately 20.5 mg/ml is prepared in 100 mM sodium phosphate buffer (pH 7.3). Gentle warming may be required to completely dissolve the product.

Substrates

Chromogenic substrate for β-galactosidase

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Choose from one of the most recent versions:

Certificates of Analysis (COA)

Lot/Batch Number

Don't see the Right Version?

If you require a particular version, you can look up a specific certificate by the Lot or Batch number.

Already Own This Product?

Find documentation for the products that you have recently purchased in the Document Library.

Visit the Document Library

D R Henderson et al.
Clinical chemistry, 32(9), 1637-1641 (1986-09-01)
Genetic engineering of beta-galactosidase (EC 3.2.1.23) has led to the development of a new homogeneous assay system, CEDIA. The Z gene of the lac operon of Escherichia coli encodes a large enzymatically inactive polypeptide that spontaneously aggregates and folds to
Steven T Bruckbauer et al.
PloS one, 14(1), e0199482-e0199482 (2019-01-24)
We have previously generated four replicate populations of ionizing radiation (IR)-resistant Escherichia coli though directed evolution. Sequencing of isolates from these populations revealed that mutations affecting DNA repair (through DNA double-strand break repair and replication restart), ROS amelioration, and cell
Superimposition of temperature regulation on yeast promoters.
A Z Sledziewski et al.
Methods in enzymology, 185, 351-366 (1990-01-01)
Receptor-mediated transport of DNA into eukaryotic cells.
M Cotten et al.
Methods in enzymology, 217, 618-644 (1993-01-01)
Gabriela N Tenea et al.
Foods (Basel, Switzerland), 9(9) (2020-09-10)
A novel Weissella cibaria strain UTNGt21O from the fruit of the Solanum quitoense (naranjilla) shrub produces a peptide that inhibits the growth of both Salmonella enterica subsp. enterica ATCC51741 and Escherichia coli ATCC25922 at different stages. A total of 31

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service