Enzyme Substrates

The sampler kit contains 10 mg each of BCIP Na (10001), BCIP Pink (10006), BCIP Red (10004) and 250 mg of NBT (10008). NBT forms a co-precipitant and enhances the BCIP reaction.

Coelenterazine and its analogs are luminescent enzyme substrates for apoaequorin and Renilla luciferase.

5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) has been used to evaluate the respiratory activity of many bacterial populations as well as populations undergoing drug efficacy evaluations.  Healthy cells respiring via the electron transport chain will absorb and reduce CTC into an insoluble, red fluorescent formazan product.

D₂R (Rhodamine 110, bis-(L-aspartic acid amide), ditrifluoroacetic acid salt) is a general substrate for caspases including caspases 3 and 7. Unlike other fluorogenic substrates for caspases, D₂R appears to be membrane-permeant, and thus can be used to measure caspase activity in live cells without osmotic shock for flow cytometry studies, as well as for cell extracts.

Dihydroethidium (also called hydroethidium) is the chemically reduced form of the commonly used DNA dye ethidium bromide. The probe is useful to detect oxidative activities in viable cells, including respiratory burst in phagocytes.

Dihydrorhodamine 123 is the reduced form of rhodamine 123 (70010), which is a commonly used fluorescent mitochondrial dye.

Dihydrorhodamine 123 dihydrochloride is functionally equivalent to dihydrorhodamine 123 (10055) but with increased stability toward air oxidation and light during storage.

DMNPE-caged D-luciferin (D-Luciferin, 1-(4,5-dimethoxy-2-nitrophenyl)ethyl ester) is a D-luciferin ester derivative which can cross cell membranes efficiently.^1,2 Once inside the cells, the ester is continuously hydrolyzed to a supply of D-luciferin.

FDP (fluorescein diphosphate, tetraammonium salt, high purity) is the most sensitive fluorogenic alkaline phosphatase substrate. It is also an excellent substrate for protein tyrosine phosphatase (PTPase) and thus the substrate of choice in the high throughput screening (HTS) for PTPase inhibitor.

Green-β-D-Gal (N-Methylindolyl-β-D-galactopyranoside) is a chromogenic substrate for β-galactosidase. Similar to X-Gal, but generates green colored precipitate on enzyme hydrolysis.

H₂DCFDA (2′,7′-Dichlorodihydrofluorescein diacetate) is a useful fluorogenic reagent to detect reactive oxygen intermediates in cells. On oxidation, H₂DCFDA becomes the highly green fluorescent 2′,7′-dichlorofluorescein.

IPTG (Isopropylthio-β-galactoside) is an inducer of β-galactosidase activity in bacteria and is suitable for use with X-gal or bluo-gal to detect lac gene activity in cloning procedures.

Cytotoxic agent that binds and inhibits dihydrofolate reductase. Useful for studying antimetabolite resistance, spontaneous gene amplification, and drug binding. Available conjugated to fluorescein and CF® Dyes.

MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) is a tetrazolium salt that is commonly used to detect reductive metabolism in cells for viability, proliferation and cytotoxicity assays. On reduction tetrazolium salts turn into deeply colored products that can be easily quantified by colorimetric measurement.

MUG (4-MU-glcUA; 4-Methylumbelliferyl-β-D-glucuronic acid dihydrate), also known as MUGlcU, is a fluorogenic β-glucuronidase substrate that releases the blue fluorescent 4-methyl-7-hydroxycoumarinon enzymatic hydrolysis. The substrate is commonly used for identifying E. coli contamination and for detecting marker GUS gene expression in plants with high sensitivity.

MUP, free acid (4-Methylumbelliferyl phosphate, free acid) is a fluorogenic phosphatase substrate that releases the blue fluorescent dye 4-methyl-7-hydroxycoumarin. MUP free acid and its salt (10010) are the most widely used fluorogenic substrates for alkaline phosphatase detection.