Fluorometric measurement of urinary N-acetyl-beta-D-glucosaminidase and its correlation to uremia.
A fluorometric endpoint method for determination of N-acetyl-beta-D-glucosaminidase (NAG, EC 3.2.1.30) activity in human urine is described. Random urine samples from uremic hospital patients and healthy volunteers were studied using 4-methylumbelliferyl-N-acetyl-beta-D-glucosaminide as substrate, from which NAG liberates 4-methylumbelliferone (4MeU) at acidic pH. The assay was accomplished on a microtiter plate and the fluorescence of 4MeU read with an automated reader after stopping the enzyme reaction at alkali pH. The NAG activities in the uremic group were about 20 times higher compared with the control group. The assay procedure is reproducible, easy to perform and shows a linear response even at high enzyme levels.
D000117:Acetylglucosamine / Q000031:analogs & derivatives*; D000118:Acetylglucosaminidase / Q000652:urine*; D000328:Adult; D002498:Centrifugation; D004912:Erythrocytes; D005944:Glucosamine / Q000031:analogs & derivatives; D006596:Hexosaminidases / Q000652:urine*; D006801:Humans; D006923:Hymecromone / Q000031:analogs & derivatives; D008875:Middle Aged; D013050:Spectrometry, Fluorescence; D014511:Uremia / Q000201:enzymology*
C025158:4-methylumbelliferyl 2-acetamido-2-deoxy-beta-D-glucopyranoside; D006923:Hymecromone; D006596:Hexosaminidases; D000118:Acetylglucosaminidase; D005944:Glucosamine; D000117:Acetylglucosamine