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Key Documents

S9811

Sigma-Aldrich

S-Gal®

reagent for selection of recombinant bacterial clones

Synonym(s):

3,4-Cyclohexenoesculetin β-D-galactopyranoside

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About This Item

Empirical Formula (Hill Notation):
C19H22O9
CAS Number:
Molecular Weight:
394.37
UNSPSC Code:
12352200
PubChem Substance ID:
NACRES:
NA.85

grade

for molecular biology

Quality Level

sterility

non-sterile

Assay

≥95% (HPLC)

form

powder

solubility

DMF: 50 mg/mL

suitability

suitable for β-galactosidase test

storage temp.

room temp

SMILES string

OC[C@H]1O[C@@H](Oc2cc3OC(=O)C4=C(CCCC4)c3cc2O)[C@H](O)[C@@H](O)[C@H]1O

InChI

1S/C19H22O9/c20-7-14-15(22)16(23)17(24)19(28-14)27-13-6-12-10(5-11(13)21)8-3-1-2-4-9(8)18(25)26-12/h5-6,14-17,19-24H,1-4,7H2/t14-,15+,16+,17-,19-/m1/s1

InChI key

HDJJDRXZHJRVGA-DIKXUDHVSA-N

General description

S-Gal® is an autoclavable, 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

Suitable for use in selection of recombinant bacterial colonies with the lac+ phenotype. S-Gal® is autoclavable and can be added to bacterial broth containing agar prior to autoclaving.
S-Gal is a patented 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.

Features and Benefits

  • More intense color contrast than X-gal
  • Excellent for use in automated colony counters
  • Autoclavable for easiest use
  • 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 is 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.

Other Notes

Autoclavable, microwavable growth medium complete with S-Gal and IPTG.
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.

Principle

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.

Reconstitution

Stock solutions of S-Gal® can be made by dissolving 50mg/ml in dimethyl formamide (DMF) and storing at -20C. Add S-Gal® (300 mg/L from stock solution ) and Ferric Ammonium Citrate (500mg/L) to agar media prior to autoclaving.

Legal Information

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

Pictograms

Exclamation mark

Signal Word

Warning

Hazard Statements

Hazard Classifications

Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3

Target Organs

Respiratory system

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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