el Moudni B, Rodier M H, Jacquemin J L
Laboratoire de Parasitologie et Mycologie Médicale, Centre Hospitalier Universitaire, La Milétrie, Poitiers, France.
Exp Parasitol. 1996 Jul;83(2):167-73. doi: 10.1006/expr.1996.0063.
N-Acetyl-beta-D-glucosaminidase activity was recovered in cell-free extracts of Trypanosoma cruzi epimastigotes. This enzyme was identified on the basis of its ability to hydrolyze the fluorogenic substrate 4-methylumbelliferyl-N-acetyl-beta-D-glucosaminide. This activity was purified to apparent homogeneity by anion exchange and molecular sieve high-performance liquid chromatography. It eluted at a native molecular weight of approximately 48,000 Da and migrated as a single band upon reducing or nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimum pH of the activity was around pH 5.4 and the enzyme gave a single peak of activity on a chromatofocusing column with an isoelectric point of 4.2. The enzyme hydrolyzed 4-methylumbelliferyl-GlcNAc, suggesting that it should be characterized as a N-acetyl-beta-D glucosaminidase, with a K(m) value of 1.5 mM from Lineweaver-Burk plots. Many inhibitors as potential enzyme effectors were investigated.
在克氏锥虫前鞭毛体的无细胞提取物中检测到了N-乙酰-β-D-氨基葡萄糖苷酶活性。该酶是根据其水解荧光底物4-甲基伞形酮基-N-乙酰-β-D-氨基葡萄糖苷的能力来鉴定的。通过阴离子交换和分子筛高效液相色谱法将该活性纯化至表观均一性。它在天然分子量约为48,000 Da时洗脱，在还原或非还原十二烷基硫酸钠-聚丙烯酰胺凝胶电泳中迁移为单一泳带。该活性的最适pH约为5.4，在等电点为4.2的色谱聚焦柱上，该酶呈现单一活性峰。该酶水解4-甲基伞形酮基-GlcNAc，表明它应被表征为N-乙酰-β-D氨基葡萄糖苷酶，根据Lineweaver-Burk图，其K(m)值为1.5 mM。研究了许多作为潜在酶效应物的抑制剂。
