How long do IPTG plates last?

Pour plates and allow to cool to room temperature (usually at least 30 minutes) before use. Spread transformed competent cells as desired. Note: Blue/White Selection plates are generally stable for only 1 week if stored at 4°C in clear sleeves, but may be stored in the dark (or a dark sleeve) at 4°C for up to 1 month.

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.

How do you make a X-gal solution?

X-gal is 5-bromo-4-chloro-3-indolyl-β-D-galactoside. 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.

Can you dissolve X-gal DMSO?

X-Gal is soluble in organic solvents such as DMSO and dimethyl formamide, which should be purged with an inert gas. The solubility of X-gal in these solvents is approximately 30 mg/ml. X-Gal is sparingly soluble in aqueous buffers.

What happens if you add too much IPTG?

If you use too much it will induce cell death, and you are wasting a such expensive material as IPTG. If your promoter works with it, I recomend inducing production with lactose, it can serve as carbon source, it is not toxic and inexpensive.

How much do IPTG plates add?

Plate Surface Add 40 µl 100mM IPTG and 120 µl X-Gal (20 mg/ml) to the surface of each plate and spread over entire surface.

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.

What is XGAL solution?

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.

How do you dissolve Iptg?

IPTG is isopropylthio-β-D-galactoside. Make a 20% (w/v, 0.8 M) solution of IPTG by dissolving 2 g of IPTG in 8 ml of distilled H2O. Adjust the volume of the solution to 10 ml with H2O and sterilize by passing it through a 0.22-µm disposable filter.

How long should you induce with IPTG?

Induce Expression (see note below) – After culture has reached OD 0.5-‐0.6 induce expression by adding IPTG to a final concentration of 0.5 mM. IPTG is a frozen solution in the -‐20oC freezer. Induce for 3 to 4 hours at 37oC with shaking.

Is IPTG stability at room temperature?

IPTG is known to be a highly stable molecule in solution at room temperature [18] and in bacterial cultures under commonly used conditions for recombinant protein production [19,20].

Why is IPTG used?

IPTG (Isopropyl ß-D-1-thiogalactopyranoside), 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.

What’s the stock concentration of X-gal for IPTG?

Typically used in conjunction with IPTG for blue/white screening via the lac operon. A typical stock concentration of X-gal is 50mM ( 20mg/mL ). To apply X-gal directly to the top of agar plates for blue/white screening, apply 40μL and wait to dry.

How does Thermo Fisher Scientific’s X-gal work?

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…

What’s the best way to apply X gal?

To apply X-gal directly to the top of agar plates for blue/white screening, apply 40μL and wait to dry. Add calculated amount of X-gal to a light-tight container. CRITICAL Container must be light-tight to avoid degradation of X-gal. Add the calculated amount of DMSO. Wait for full dissolution. OPTIONAL Distribute into smaller aliquots for storage.

How long do IPTG plates last? Pour plates and allow to cool to room temperature (usually at least 30 minutes) before use. Spread transformed competent cells as desired. Note: Blue/White Selection plates are generally stable for only 1 week if stored at 4°C in clear sleeves, but may be stored in the dark (or a…