How do you dissolve X-gal?
Make a 2% (w/v) stock solution by dissolving X-gal in dimethylformamide at a concentration of 20 mg/ml solution. Use a glass or polypropylene tube. Wrap the tube containing the solution in aluminum foil to prevent damage by light and store at -20°C. It is not necessary to sterilize X-gal solutions by filtration.
What is the chemical name of X-gal?
3-Indolyl β-D-Galactopyranoside
X-Gal (5-Bromo-4-Chloro-3-Indolyl β-D-Galactopyranoside)
What is the function of X-gal?
X-Gal is a cell permeable, chromogenic substrate for β-galactosidase. It consits of galactose linked to a substituted indole. β-galactosidase hydrolyzes X-gal to release an insoluble, bright blue precipitate. X-Gal is frequently used in molecular biology cloning applications to detect the activity of β-galactosidase.
What is X-gal staining?
X-gal staining is a rapid and convenient histochemical technique used to detect reporter gene expression. Expression is marked by a dark blue stain and can be detected at the single cell level, providing a robust visual readout of gene expression in the developing kidney.
Is XGAL toxic?
Acute toxicity : Oral: Harmful if swallowed. Dermal: Harmful in contact with skin. Inhalation: Harmful if inhaled. Potential adverse human health effects and symptoms : Dust in eyes may cause mechanical irritation.
How long does XGAL last?
X-Gal Solution is stable for 6-12 months at -20°C. However, frequent use will cause degradation of the solution over time and we recommend making new stocks every 2-3 months depending on use.
Why is XGL blue?
If β-galactosidase is produced, X-gal is hydrolyzed to form 5-bromo-4-chloro-indoxyl, which spontaneously dimerizes to produce an insoluble blue pigment called 5,5′-dibromo-4,4′-dichloro-indigo. The colonies formed by non-recombinant cells, therefore appear blue in color while the recombinant ones appear white.
What is beta-galactosidase assay?
β-Galactosidase converts the colorless ONPG substrate into galactose and the chromophore o-nitrophenol, yielding a bright yellow solution. The β-Galactosidase Assay Kit is excellent for determining enzyme activity in lysates from cells transfected with a β-galactosidase expression construct.
Why does XG turn blue?
The ‘X’ in X-gal is a colorless pigment when attached to the galactose sugar but turns blue when cleaved by beta galactosidase. The blue color pigment will form in the cells and blue colonies are formed on the plates.
What is LacZ used for?
The use of a reporter gene can allow for examination of spatial patterns of gene expression of a particular promoter within a tissue, embryo, or adult mouse.
What does IPTG stand for?
Isopropyl β- d-1-thiogalactopyranoside
Isopropyl β- d-1-thiogalactopyranoside (IPTG) is a molecular biology reagent. This compound is a molecular mimic of allolactose, a lactose metabolite that triggers transcription of the lac operon, and it is therefore used to induce protein expression where the gene is under the control of the lac operator.
At what temperature does kanamycin degrade?
Kanamycin activity is stable at ph 7.3 and 72 degrees C. The half-life (t1/2) at pH 7.3 and 72 degrees C ranged from 3.3 h (k = 7.26 day-1, where k [degradation constant] = 1/t1/2) for ampicillin to no detectable loss of activity for kanamycin, neomycin, and other antibiotics.
How many mg of X-gal is in DMF?
A stock solution of X-gal is commonly made with 20 mg/ml X-gal in DMF (dimethylformamide). When pouring agar plates, a typical final concentration is 20 μg/ml. Note that DMF is toxic.
How is X-gal stored in DMSO storage conditions?
X-gal in DMSO storage conditions -. We recently dissolved our X-gal powder in DMSO instead of DMF, as it was before, because it is less toxic, and sparing all the troubles of getting it from the locker in the basement. It was stored in -20. But colleague was not as happy with the fact that DMSO freezes at -20, also people usually store it in
What do you need to know about X-gal?
Jump to navigationJump to search. X-Gal is the common short name for 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside. It is a substrate for beta-galactosidase (lacZ) and turns blue upon being cleaved. It is commonly used for blue-white screening or detection of LacZ transgenes in cells and tissues.
Where does the chemical name X gal come from?
The compound was synthesized by Jerome Horwitz and collaborators in Detroit, MI, in 1964. The formal chemical name is often shortened to less accurate but also less cumbersome phrases such as bromochloroindoxyl galactoside. The X from indoxyl may be the source of the X in the X-gal contraction.