S7313

S-Gal^® sodium salt

reagent for selection of recombinant bacterial clones

• Synonyme(s) : 3,4-Cyclohexeneoesculetin-B-D-galactopyranoside sodium salt
• Formule empirique (notation de Hill): C₁₉H₂₁O₉Na
• Poids moléculaire : 416.35
• Numéro MDL: MFCD03458481
• Code UNSPSC : 12352200
• Nomenclature NACRES : NA.85

Propriétés

• Qualité: for molecular biology
• Stérilité: non-sterile
• Pureté: ≥95% (HPLC)
• Forme: powder
• IVD: not for in vitro diagnostic use
• Solubilité: H₂O: 100 mg/mL
• Adéquation: suitable for β-galactosidase test
• Température de stockage: room temp

Description

Description générale

S-Gal^® (sodium salt) is an autoclavable, water-soluble, chromogenic substrate for β-galactosidase, used to determine the presence or absence of a cloned DNA insert in bacteria growing on agar plates. S-gal^® is designed to replace X-Gal in blue-white selection of recombinant bacterial colonies with the lac+ phenotype.

Application

S-Gal, sodium salt is a patented water-soluble, autoclavable chromogenic substrate for β-galactosidase that is designed to replace X-Gal in blue-white selection of recombinant bacterial colonies with the lac⁺ phenotype.

Caractéristiques et avantages

• More intense color contrast than X-gal
• Water-soluble and autoclavable for easiest use
• Excellent for use in automated colony counters
• No need to make stock solutions

When S-Gal is cleaved by β-galactosidase, the resulting product will chelate ferric ion to create a black, insoluble precipitate. Lac⁺ colonies grown in the presence of S-Gal and ferric ion turn an intense black color, allowing for easy differentiation between lac⁺ and lac^- colonies. S-Gal, Sodium salt is water soluble, eliminating the need for solvents such as dimethyl formamide. S-Gal is also autoclavable and can be added to your medium of choice prior to autoclaving. S-Gal is not light sensitive and does not require any protection from light sources.

Autres remarques

More water soluble version, soluble >50 mg/mL.

The ferric or Fe³⁺ ion is required for color development and must be added to any S-Gal^®
formulation. A medium prepared with S-Gal^® is moderately dark due to the presence of ferric ammonium citrate. This darker background often provides enhanced contrast for automated colony counting or isolation.

Attention

For black color development to occur, ferric ion must be present. Although we recommend ferric ammonium citrate (500 mg/L of media), other ferric compounds can be used to provide this requirement, depending upon your particular system.

Principe

When S-Gal^® is cleaved by ß-galactosidase, the resulting product will chelate ferric ion to create a black, insoluble precipitate. Lac+ colonies grown in the presence of S-Gal^® and ferric ion turn an intense black color, allowing for easy differentiation between lac+ and lac- colonies.

Liaison

Ferric Ammonium Citrate (F5879), LB Agar (L2897), IPTG (Isopropyl β-D-thiogalactopyranoside, I6758), Ampicillin (A2804), Kanamycin (K0879), Chloramphenicol (C7795), Tetracycline (T8032)

Reconstitution

Add to agar media pre-autoclaving at a recommended concentration of 300 mg S-Gal/L of media, along with 500 mg/L Ferric Ammonium Citrate (F5879). Stock solutions of S-Gal can be made by dissolving at 50 mg/mL in deionized water, sterile-filtering and storing at -20 °C.

Stock solutions of S-Gal^® (sodium salt) can be made by dissolving 50mg/ml in water, dimethyl formamide (DMF) or DMSO. Filter sterilize and store at -20C. Add S-gal^® (300 mg/L from stock solution or powder) and Ferric Ammonium Citrate (500mg/L) to agar media prior to autoclaving.

Informations légales

S-GAL is a registered trademark of Merck KGaA, Darmstadt, Germany

Informations sur la sécurité

• Code de la classe de stockage: 11 - Combustible Solids
• Classe de danger pour l'eau (WGK): WGK 3
• Point d'éclair (°F): Not applicable
• Point d'éclair (°C): Not applicable
• Équipement de protection individuelle: Eyeshields, Gloves, type N95 (US)