Y‑GlcA Sodium Salt

Y‑GlcA Sodium Salt (CAS 119736‑51‑5), systematically 3‑indolyl‑β‑D‑glucuronic acid sodium salt, is a synthetic β‑D‑glucuronidase‑specific chromogenic substrate in which a 3‑indolyl (indoxyl) aglycone is linked via a β‑glycosidic bond to β‑D‑glucuronic acid and presented as the sodium salt. When hydrolyzed by β‑D‑glucuronidase (EC 3.2.1.31, GUS), the indoxyl moiety is released and undergoes aerial oxidation to form an insoluble yellow‑to‑brownish precipitate, enabling clear visual detection of enzyme activity. The sodium‑salt form improves water solubility, making it suitable for use directly in aqueous buffers and agar‑based systems. Y‑GlcA Sodium Salt is used in selective culture media for β‑glucuronidase‑producing bacteria, in GUS‑reporter‑gene assays for plant and bacterial systems, and in histochemical staining of GUS activity in tissues and cell cultures. The yellow/brown dye contrasts with blue‑forming substrates such as X‑GlcA and Salmon‑GlcA, enabling multiplex detection or color‑coding of different enzyme activities. The compound is compatible with standard microbiological and molecular‑biology buffers and is supplied as a crystalline, high‑purity powder optimized for chromogenic solid‑medium and reporter‑gene applications.

Appearance

• Off‑white to pale yellow crystalline or lyophilized powder.
• Forms a clear, yellow‑tinted solution in aqueous buffer, with the true chromogenic color (yellow‑to‑brown) appearing only after enzymatic hydrolysis and oxidation.

Source / synthesis

• Synthetically produced by coupling 3‑indoxyl with β‑D‑glucuronic acid and then converting the free acid into its monosodium salt form to enhance water solubility.
• Commercially manufactured by specialty enzyme‑substrate suppliers (e.g., GeneseqTools, Hepattack, ChemicalBook‑listed vendors) as a high‑purity GUS‑assay reagent.

Molecular weight and structure

• Molecular formula: C14H14NNaO7C14H14NNaO7.
• Molecular weight: 331.25 g/mol.
• Structure: 1H‑indol‑3‑yl β‑D‑glucopyranuronate monosodium salt, with a β‑glycosidic linkage between the indole C3‑O and the D‑glucuronic‑acid ring.

Sugar specificity

• Specifically hydrolyzed by β‑D‑glucuronidases (GUS, EC 3.2.1.31) and β‑glucuronide‑cleaving enzymes.
• Shows minimal cross‑reactivity with other β‑glycosidases under standard assay conditions, providing high selectivity for β‑glucuronidase activity.

Biological activity

• Acts as a chromogenic reporter for β‑glucuronidase‑mediated hydrolysis of β‑D‑glucuronosyl linkages in glucuronides and glycosaminoglycan‑derived substrates.
• Enzymatic cleavage releases 3‑indoxyl, which oxidizes and dimerizes into a yellow‑to‑brown, water‑insoluble dye, enabling sensitive detection in bacterial colonies, plant‑tissue GUS assays, and histological sections.

Purity and microbial contamination

• Typically supplied at ≥95–98% purity as indicated by HPLC or similar analytical methods on vendor data sheets.
• Described as non‑sterile, research‑grade material with low microbial contamination status, suitable for microbiological and biochemical use under standard aseptic conditions.

Identity and quality control

• Identity inferred from molecular formula, molecular weight, and spectral data (UV/Vis, NMR, HPLC) consistent with 3‑indolyl‑β‑D‑glucuronic acid sodium salt.
• Quality‑control procedures include checks for appearance, solubility, and performance in a defined β‑glucuronidase (e.g., E. coli GUS⁺) activity assay on plates or in solution.

Shelf life and storage

• Shelf life is generally 12–24 months when stored as a dry powder at –20 °C in a tightly sealed, desiccated container, protected from moisture and light.
• Stock solutions in water or buffer should be prepared immediately before use or stored frozen for short periods to minimize degradation and nonspecific oxidation of the indoxyl moiety.

Application

• Screening and identification of β‑glucuronidase‑positive bacteria (e.g., certain E. coli strains) on selective agar media.
• GUS‑reporter assays for detection of β‑glucuronidase gene expression in bacterial, yeast, and plant systems.
• Histochemical or cytochemical localization of GUS activity in tissue sections and cell preparations where a yellow/brown dye is preferred over blue.

Key characteristics

• Produces a yellow‑to‑brown insoluble dye upon β‑glucuronidase hydrolysis, providing a color‑distinct alternative to blue‑forming GUS substrates.
• Defined β‑D‑glucuronide linkage with a sodium counterion, improving water solubility over the free‑acid form.
• Crystalline, stable powder with a known molecular formula and weight, suitable for quantitative GUS assays and standardized media formulations.

Citations

• ChemicalBook – 3‑Indoxyl‑β‑D‑glucuronic acid, sodium salt (Y‑GlcA Sodium Salt, CAS 119736‑51‑5, MF C₁₄H₁₄NNaO₇, MW 331.25): https://www.chemicalbook.com/ChemicalProductProperty_EN_CB7424438.htm
• GeneseqTools – Product list entry for Y‑GlcA Sodium Salt (CAS 119736‑51‑5) alongside other chromogenic GUS substrates: http://www.geneseqtools.cn/en/product02_cid_306.html
• Hepattack – Products‑page listing Y‑GlcA Sodium Salt (CAS 119736‑51‑5) as a GUS‑chromogenic substrate: https://www.hepattack.com/en/product02_cid_306.html
• General enzyme‑substrate catalog (chromogenic β‑glucuronidase substrates including Y‑GlcA and related analogs): https://www.chemicalbook.com/ (search for “119736‑51‑5”)
• 3‑Indoxyl‑β‑D‑glucuronic acid sodium salt technical‑data overview (formula, MW, and CAS details): https://webbook.nist.gov/ (search for “119736‑51‑5” or “3‑indolyl‑β‑D‑glucuronic acid sodium salt”)
• β‑Glucuronidase and GUS‑substrate review (for enzyme‑application context): https://www.ncbi.nlm.nih.gov/pmc/ (search for “β‑glucuronidase substrate”)
• X‑GlcA Sodium Salt product listings (for dye‑chemistry and assay‑format reference): https://www.sigmaaldrich.com/ (search for “X‑GlcA sodium salt”)
• Glentham or similar enzyme‑substrate homepage (indolyl‑β‑D‑glucuronide series overview): https://www.glentham.com/en/products/
• ScienceDirect – Chromogenic substrate overview (for classification and assay‑principle background): https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/chromogenic-substrate
• β‑Glucuronidase applications in food and biotechnology (PMC‑type review for enzyme‑context): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5429307/ (or similar PMC article on glycosidase applications)