Other Enzyme Substrates

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.

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.

MUP, Na (4-Methylumbelliferyl phosphate, disodium salt) is the sodium salt of MUP. MUP sodium salt and MUP free acid (#10009) are the most widely used fluorogenic substrates for alkaline phosphatase detection.

A functionalized version of NAD containing an amino group that permits it to be fixable in a gel matrix. This property makes NAD-hexylamine useful for constructing wearable biosensors that comprise a dehydrogenase enzyme such as diaphorase.

NBT (Nitro blue tetrazolium, chloride) is an oxidant and is widely used in conjunction with BCIP or BCIP derivatives to detect phosphatase activity. NBT is also a substrate for dehydrogenate and other oxidizes.

Purple-β-D-Gal (5-Iodo-3-indolyl-β-D-galactopyranoside) is a chromogenic substrate for β-galactosidase. Similar to X-gal, but generates a purple (λ_max ~575 nm) colored precipitate on enzyme hydrolysis.

Red-β-D-Gal (5-Bromo-6-chloro-3-indolyl-β-D-galactopyranoside) is a chromogenic substrate for β-galactosidase. Similar to X-gal, but generates a red or magenta (λ_max ~ 565 nm) colored precipitate on enzyme hydrolysis.