Yamada Magohei, Fujita Toshio
International Reagents Company, Ltd., Kobe, Japan.
J Clin Lab Anal. 2003;17(4):127-31. doi: 10.1002/jcla.10080.
2,4-Dinitrophenyl-1-thio N-acetyl-beta-D-glucosaminide was examined as a new substrate for analyzing the level of N-acetyl-beta-D-glucosaminidase in the urine of patients suffering from renal diseases. The analysis is based on the fact that the substrate, when hydrolyzed in the presence of N-acetyl-beta-D-glucosaminidase, liberates 2,4-dinitrothiophenol as the chromogen. The optimum pH for the enzyme reaction is 4.6, which is covered by the optimal range for the UV absorbance of the chromogen. The first-order rate of increase of the absorbance at this pH was linear to the enzyme concentration up to 600 U/L, with a high sensitivity. Analytical reagents with glucosaminides of 2,4-dinitrophenol and 2-chloro-4-nitrophenol are less stable than the reagent with glucosaminide of 2,4-dinitrothiophenol. The optimum pH for the absorbance of p-nitrophenol and 2-chloro-4-nitrophenol does not match that for the enzyme reaction.
对2,4-二硝基苯基-1-硫代-N-乙酰-β-D-氨基葡萄糖苷作为一种分析肾病患者尿液中N-乙酰-β-D-氨基葡萄糖苷酶水平的新底物进行了研究。该分析基于这样一个事实，即该底物在N-乙酰-β-D-氨基葡萄糖苷酶存在下被水解时，会释放出2,4-二硝基硫代苯酚作为显色剂。酶反应的最适pH为4.6，这在显色剂的紫外吸收最佳范围内。在此pH下吸光度的一级增加速率在酶浓度高达600 U/L时与酶浓度呈线性关系，具有高灵敏度。含2,4-二硝基苯酚和2-氯-4-硝基苯酚氨基葡萄糖苷的分析试剂不如含2,4-二硝基硫代苯酚氨基葡萄糖苷的试剂稳定。对硝基苯酚和2-氯-4-硝基苯酚吸光度的最适pH与酶反应的最适pH不匹配。
