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X-Gal / 5-Bromo-4-chloro-3-indolyl-b-D-galactopyranoside

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Product number: M3204.0001
Delivery time: 3- 8 working days
For detailed information on the delivery date, please contact Genaxxon.

Shipment: not cooled. Store at -20°C. For laboratory usage only!
Product information "X-Gal / 5-Bromo-4-chloro-3-indolyl-b-D-galactopyranoside"

X-Gal (5-Brom-4-chlor-3-indolyl-β-D-galactopyranosid) is a chromogenic substrate for β-galactosidase. It produces a blue color that can easily be detected visually. X-Gal is used in the identification of lacZ + bacteria, especially for the detection of ß-galactosidase, which is expressed by the recombinant vectors. X-Gal is often used in conjunction with IPTG > (for the induction of the lac promoter (lac operon)), for the screening of blue colonies. It is also used for the screening of ß-galactosidase reporter gene activity in transfections of eukaryotic cells.

X-Gal is a substrate of ß-galactosidase, which releases by cleavage of the substrate 5-bromo-4-chloro-3-indoxyl (X). The enzymatically cleaved indoxyl is oxidized to the insoluble indigo. As a stock solution, for example, a 20mg/mL X-Gal solution in dimethylformamide can be prepared. For the use in LB / Amp - plates this stock solution is to be diluted 1 : 1000 (final concentration 20μg/mL) or 1: 500 (final concentration 40μg/mL). The heated medium should thereby be cooled to about 50°C. The amount of X-Gal may be reduced if an X-Gal solution in DMF is sprayed to the agar plates (already with bacterial colonies!). X-Gal is the substrate of choice for blue-white selection of recombinant bacterial colonies with the lac+ genotype.

Assay: min. 98% (HPLC)
Appearance: white to off-white powder
MP: 223°C
a20°C/D (1%, 50% DMF): -62° +/- 2°
Water (K.F.): max: 1%
MW = 408.6 g/mol

Applikation / Application:
- 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.

Einheiten / Units:
Quelle / Source:

Sicherheits Hinweise / Safety

Klassifizierungen / Classification

EC-Nr: 230-640-8
CAS-Nr: 7240-90-6
eclass-Nr: 32-16-06-90
Documents - Protocols - Downloads :
Here you will find information and further literature. For further documents (certificates with additional lot numbers, safety data sheets in other languages, further product information) please contact Genaxxon biosience at: info@genaxxon.com or phone: +49 731 3608 123.


Safety Data Sheet
Category List
Listed below are articles and references, in which the authors trust in the high quality of this Genaxxon product.
Source: NCBI PubMed