B3928

Blue-White Select^™ Screening Reagent

for selection of recombinant bacterial clones

• Synonyme(s) : Blue-White Reagent, Screening Reagent, Selection Reagent
• Code UNSPSC : 12352200
• Nomenclature NACRES : NA.85

Propriétés

• Qualité: for molecular biology
• Niveau de qualité: 200
• Forme: liquid
• Utilisation: sufficient for 125 dishes (90 mm)
• Technique(s): nucleic acid detection: suitable
• Adéquation: suitable for nucleic acid staining
• Conditions d'expédition: dry ice
• Température de stockage: −20°C

Description

Description générale

Sigma′s Blue-White Select^™ Screening Reagent is a chromogenic substrate for β-galactosidase, used to determine the presence or absence of a cloned DNA insert in bacteria growing on agar plates. Blue-White Select^™ Screening Reagent is designed for blue-white selection of recombinant bacterial colonies with the lac+ phenotype.

Caractéristiques et avantages

• Intense color contrast for easy colony selection
• Convenient, ready-to-use solution

Composants

40 mg/mL IPTG
40 mg/mL X-Gal
(prepared in DMSO)

Principe

When Blue-White Select^™ Screening Reagent is cleaved by β-galactosidase, the resulting product will form a blue precipitate. Lac+ colonies grown in the presence of Blue-White Select^™ Screening Reagent remain white in color, allowing for easy differentiation between lac+ and lac- colonies.

The technique is based on vectors such as the pUC and the M13mp series that carry a fragment of the β-galactosidase gene encoding an a-fragment of β-galactosidase. Exploitation of these vectors requires use of a bacteria strain carrying the complementing gene fragment to allow the assembly of an active complex, resulting in the formation of blue colonies. Disruption of the ß-galactosidase gene by insertion of a DNA fragment into the vector′s multiple cloning site results in the loss of functional β-galactosidase activity; these colonies remain white, allowing for easy differentiation between lac+ and lac- colonies.

Informations légales

Blue-White Select is a trademark of Sigma-Aldrich Co. LLC

Informations sur la sécurité

• Code de la classe de stockage: 10 - Combustible liquids
• Classe de danger pour l'eau (WGK): WGK 3
• Point d'éclair (°F): 188.6 °F
• Point d'éclair (°C): 87 °C
• Équipement de protection individuelle: Eyeshields, Gloves, type ABEK (EN14387) respirator filter