Shop All Beta-Galactosidase Substrates

DDAO galactoside (9H-(1,3-Dichloro-9,9-Dimethylacridin-2-One-7-yl) β-D-Galactopyranoside) (Invitrogen™)

The galactosidase substrate, DDAO galactoside yields a hydrolysis product that can be excited with the 633 nm laser (excitation/emission maxima ~645/660). Although the substrate itself is fluorescent (excitation/emission maxima ~460/610 nm), the difference between the substrate's and the hydrolysis product is over 200 nm, along the two species to be easily distinguished.

Fluorescein Di-β-D-Galactopyranoside (FDG) (Invitrogen™)

Fluorescein di-β-D-galactopyranoside (FDG) is one of the most sensitive substrates for galactosidases. Nonfluorescent FDG is sequentially hydrolyzed by β-galactosidase, first to fluorescein monogalactoside (FMG) and then to highly fluorescent fluorescein. Enzyme-mediated hydorlysis of FDG can be followed by the increase in either absorbance or fluorescence.

X-Gal (5-Bromo-4-Chloro-3-Indolyl β-D-Galactopyranoside) (Invitrogen™)

X-Gal is a widely used chromogenic substrate for β-galactosidase. It yields a dark blue precipitate at the site of enzymatic activity. X-Gal is useful for numerous histochemical and molecular biology applications, including detection of lacZ activity in cells and tissues. In contrast to β-glucuronidase as a gene marker, β-galactosidase can be fixed in cells and tissues with glutaraldehyde without loss of activity and detected with high resolution using X-Gal.


• Chromogenic substrate
• Cell permeant
• β-galactosidase activity can still be detected using X-Gal after fixation


Additional Information About Glycosidase Enzymes
Glycosidase enzymes exhibit very high selectivity for hydrolysis of their preferred sugars. For example, β-galactosidase rapidly hydrolyzes β-D-galactopyranosides but usually does not hydrolyze either the anomeric α-D-galactopyranosides or the isomeric β-D-glucopyranosides. Endogenous glycosidase activity is frequently used to characterize strains of microorganisms and to selectively label organelles of mammalian cells; defects in glycosidase activity are characteristic of several diseases.

In addition, glycosidases are important reporter gene markers. Specifically, lacZ, which encodes β-galactosidase, is extensively used as a reporter gene in animals and yeast, whereas the β-glucuronidase (GUS) gene is a popular reporter gene in plants. Glycosidase substrates are also used in conjunction with glycosidase-conjugated secondary detection reagents in immunohistochemical techniques and enzyme-linked immunosorbent assays (ELISAs). See all of our Molecular Probes® fluorogenic and chromogenic glycosidase substrates.

For Research Use Only. Not for human or animal therapeutic or diagnostic use.

Galacton-Plus™ Substrate (100X Concentrate) (Invitrogen™)

The Galacton-Plus® Substrate is a concentrated chemiluminescent substrate for E.coli β-galactosidase assays.

For Research Use Only. Not for use in diagnostics procedures.

X-Gal (Thermo Scientific™)

Thermo Scientific X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galacto-pyranoside) is an inert chromogenic substrate for beta-galactosidase which hydrolyzes X-Gal into colorless galactose and 4-chloro-3-brom-indigo, forming an intense blue precipitate. Induction of the lacZ gene with IPTG leads to the hydrolysis of X-Gal and to the development of blue colonies (see Supporting data).

Applications

• Blue/white colony screening to distinguish recombinant (white) from non-recombinant (blue) colonies (see Reference 1)
• Visualization of beta-galactosidase reporter gene expression in transfected eukaryotic cells
• Detection of beta-galactosidase activity in immunological and histochemical procedures

Note
• Preparation of a 20 mg/mL stock solution in dimethylformamide (DMF) or dimethylsulfoxide (DMSO) is recommended for X-Gal. DMF dissolves some plastic materials. The direct addition of DMF containing solution to plastic Petri dishes should be avoided.
• DMF is toxic. Allow X-Gal solution containing dimethylformamide to completely dry before plating bacteria on agar plates.

Related Products
X-Gal
X-Gal Solution, ready-to-use

Galacto-Light™ Reaction Buffer Diluent with Galacton-Plus™ Substrate (Invitrogen™)

The Galacto-Light™ Reaction Buffer Diluent and the Galacton-Plus™ chemiluminescent substrate solution are used with the Galacto-Light™ Plus Reporter Gene Assay System.

Use With
Light Emission Accelerator-II

For Research Use Only. Not for use in diagnostics procedures.

C12FDG (5-Dodecanoylaminofluorescein Di-β-D-Galactopyranoside) (Invitrogen™)

The β-galactosidase substrate, C12FDG has been covalently modified to include a 12-carbon lipophilic moiety. Once inside the cell, the substrate is cleaved by β-galactosidase producing a fluorescent product that is well retained by the cells, probably by incorporation of the liphophilic tail within the cell membrane. C12FDG is the main component in the ImaGene™ Green kit.

Galacton-Star™ Substrate (50X Concentrate) (Invitrogen™)

Galacton-Star Substrate is a chemiluminescent substrate designed for the rapid, sensitive detection of β-galactosidase in cell lysates. The chemiluminescent assay exhibits over three orders of magnitude greater sensitivity compared to colorimetric β-galactosidase assays. Light emission from Galacton-Star Substrate reaches a maximum in 60-90 minutes and remains constant for at least 1 hour. After incubation at room temperature, the signal is measured in a luminometer.

As few as 10 femtograms of β-galactosidase (20,000 molecules) are detectable. High sensitivity makes this substrate ideal for detection of weak expression and for transfection normalization with other sensitive reporter gene assays.

ONPG (o-nitrophenyl-β-D-galactopyranoside) (Thermo Scientific™)

Thermo Scientific Pierce ONPG is the preferred colorimetric substrate for ELISA applications involving beta-galactosidase (b-Gal) as the reporter enzyme.

When using beta-Galactosidase as the label for proteins in ELISA studies, a wide variety of substrates are available, including: o-Nitrophenyl-beta-D-galactopyranosidase (ONPG), Naphthol-AS-Bl-beta-D-galactopyranosidase (Nap-Gal), and 4-Methyl-umbelliferyl-beta-D-galactopyranosidase (MUm-Gal). However, it is important to choose a substrate with adequate solubility, that uses readily available equipment, and that gives a significant reading over the background. ONPG is a superior beta-Galactosidase substrate option.(1) The product formed is completely soluble and has a high extinction coefficient at 405nm. The substrate yields a yellow product that is easily detectable in the visual range after stopping the reaction with 1M Sodium Carbonate.

Galacto-Star™ Reaction Buffer Diluent with Galacton-Star™ Substrate (Invitrogen™)

This is the Galacton-Star® chemiluminescent substrate solution and substrate dilution buffer for the detection of E. coli β-galactosidase for use with the Galacto-Star™ One-Step β-Galactosidase Reporter Gene Assay System.

For Research Use Only. Not for use in diagnostics procedures.

Resorufin β-D-Galactopyranoside (Invitrogen™)

The fluorogenic β-galactosidase substrate resorufin β-D-galactopyranoside yields the hydrolysis product, resorufin, with absorption/emission maxima at 571/585 nm.

Bluo-Gal, substrate for β-galactosidase (Invitrogen™)

Bluo-gal (halogenated indolyl-β-galactoside) is an alternative histochemical substrate for β-galactosidase that produces a darker blue color than X-gal, the more frequently used substrate. β-galactosidase hydrolyzes bluo-gal to produce a blue precipitate that is insoluble in alcohol and xylenes and is suitable for immunoblotting and immunocytochemical assays. Bacteria containing active β-galactosidase produce blue colonies when grown on plates containing bluo-gal. Bluo-gal is soluble in dimethylformamide.

X-Gal Solution, ready-to-use (Thermo Scientific™)

Thermo Scientific X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galacto-pyranoside) is an inert chromogenic substrate for beta-galactosidase which hydrolyzes X-Gal into colorless galactose and 4-chloro-3-brom-indigo, forming an intense blue precipitate. Induction of the lacZ gene with IPTG leads to the hydrolysis of X-Gal and to the development of blue colonies (see Supporting data).

X-Gal Solution, ready-to-use, is stable, 0.22 µm membrane filtered solution formulated for direct use in conjunction with IPTG for blue/white colony screening.

Applications

• Blue/white colony screening to distinguish recombinant (white) from non-recombinant (blue) colonies
• Visualization of beta-galactosidase reporter gene expression in transfected eukaryotic cells
• Detection of beta-galactosidase activity in immunological and histochemical procedures

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X-Gal