Glycosidase enzymes and their fluorogenic and chromogenic substrates—Table 10.1

Table 10.1 Glycosidase enzymes and their fluorogenic and chromogenic substrates.

Carbohydrate (Enzyme)	Notes on Enzyme Activity	Labeled Substrate (Abs/Em of the products) *		Cat #
β-D-Galactopyranoside (β-Galactosidase, E.C. 3.2.1.23)	Useful as a reporter gene marker Useful for ELISAs Useful for enumerating coliforms from the family Enterobacteriaceae Useful for classifying mycobacteria	Blue-fluorescent product	4-Methylumbelliferyl (360/449)	M1489MP
		Green-fluorescent product	Fluorescein (490/514)	F1179
			5-(Pentafluorobenzoylamino)-fluorescein (490/514)	P11948
			C₂-Fluorescein (490/514)	A22010
			C₁₂-Fluorescein (490/514)	D2893, I2904 ‡
			5-Chloromethylfluorescein (490/514)	D2920 †
		Red-fluorescent product	C₁₂-Resorufin (571/585)	I2906 ‡
			DDAO (646/659)	D6488
			Resorufin (571/585)	R1159
		Chromogenic substrate	5-Bromo-4-chloro-3-indoyl (615/NA)	X-Gal; B1690
β-D-Glucopyranoside (β-Glucosidase, E.C. 3.2.1.21)	Deficiency in acid β-glucosidase, which leads to abnormal lysosomal storage, characterizes Gaucher disease Useful as a marker for the endoplasmic reticulum	Green-fluorescent product	Fluorescein (490/514)	F2881
β-D-Glucopyranoside (β-Glucosidase, E.C. 3.2.1.21)		Green-fluorescent product	5-(Pentafluorobenzoylamino)fluorescein (490/514)	P11947
β-D-Glucuronide (β-Glucuronidase, GUS; E.C. 3.2.1.31)	Useful as a reporter gene marker Useful as a lysosomal marker Useful for detecting E. coli; 94–96% of E. coli contain this enzyme, but it is less common in Shigella (44–58%), Salmonella (20–29%) and Yersinia strains	Blue-fluorescent product	4-Methylumbelliferyl (360/449)	M1490
		Green-fluorescent product	Fluorescein (490/514)	F2915
			5-(Pentafluorobenzoylamino)fluorescein (490/514)	P11949
			C₁₂-Fluorescein (490/514)	I2908 ‡
		Chromogenic substrate	5-Bromo-4-chloro-3-indoyl (615/NA)	X-GlcU, B1691
* Approximate absorption (Abs) and fluorescence emission (Em) maxima of enzymatic hydrolysis product, in nm. † DetectaGene Green Gene Expression Kit. ‡ ImaGene Green or ImaGene Red Gene Expression Kit. NA = Not applicable.