Studies on glucosaminidase. 4. The fluorimetric assay of N-acetyl-β-glucosaminidase

Abstract

Mead, Smith & Williams (1955) introduced a method for the fluorimetric assay of ,B-glucuronidase activity; the method consisted of the enzymic hydrolysis of methylumbelliferyl (3glucuronide, followed by fluorimetric estimation of the liberated methylumbelliferone. Robinson (1956) synthesized methylumbelliferyl (3-glucoside and used it in the study of ,B-glucosidases from a variety of sources; like Mead et al. (1955), Robinson found the fluorogenic method convenient and extremely sensitive. Levvy, Hay & Marsh (1957) attempted to use methylumbelliferyl ,B-glucuronide in the study of limpet fl-glucuronidase; they found methylumbelliferone to be unstable, and so considered the method to be too exacting for general use.

Tay‐sachs disease and related disorders: Fractionation of brain N‐acetyl‐β‐hexosaminidase on DEAE‐cellulose

“…The method was a modification of that of Leaback and Walker [8] : enzyme solution (100 /.d) was incubated with 3 mM 4-methyl-umbellifery12-acetamido-2-deoxy_P-D-glucopyranoside (Koch-Light Laboratories Ltd) in sodium phosphate-citrate buffer, pH 4.5 [9] (100 ~1) at 37" for 20 min; 0.25 M glycine adjusted to pH 10.4 with NaOH (1 .O ml) was then added and the fluorescence measured in an Aminco-Bowman spectrofluorimeter, excitation, 360 nm; emission, 440 nm.…”

Effects of Tumour Cell Culture Supernatants on Some Biochemical Activities of Macrophages

“…Acid phosphatase, i3-D-gIucuronidase and N-acetyl-D-glucosaminidase activities were assayed by the fluorimetric measurement of the hydrolysis of 4-methylumbelIiferyl (4-MU) derivatives to the parent 4-MU molecule (Mead, Smith and Williams, 1955;Leaback and Walker, 1961). The test samples were incubated with the appropriate derivative at 37° for a timed period.…”

Activity of Hydrolytic Enzymes in Various Regions of Normal Human Brain Tissue

“…Assay was carried out using the method described earlier [21,22] subsequently modified with 0.52 mmol/L 4-methyl umbelliferyl N-acetyl-b-D-Glucosaminide (SIGMA). The supernatant tissue extract of 20 ll was pre incubated at 37°C for 5 min and 40 ll substrate was added to initiate the enzyme action and readings taken after 60 min at 37°C.…”