γ-Glutamyltranspeptidase (γ-GT) from human esophageal cancer, normal esophageal mucosa and normal kindney were partially purified and their biochemical and immunological properties were studied. (1) The γ-GT activi...γ-Glutamyltranspeptidase (γ-GT) from human esophageal cancer, normal esophageal mucosa and normal kindney were partially purified and their biochemical and immunological properties were studied. (1) The γ-GT activity of esophageal cancer was higher than that of normal mucosa, yet still much lower than that of normal kidney. (2) The Michaelis constant and optimum pH of esophageal cancer γ-GT were the same as those of normal kidney tissue. (3) After staining of γ-GT activity, two molecular clusters, i.e. 100kD and 380kD γ-GT were shown in esophageal cancer by 4-20% linear gradient PAGE and the lOOkD γ-GT showed higher activity. (4) The γ-GT of esophageal cancer was immunologically identical with normal enzyme in double immunodif-fusion and immunoelectrophoresis. (5) In double lectin-diffusion, affinity column and crossed immuno-affino-electrophoresis, it was demonstrated that the carbohydrate components of γ-GT from esophageal cancer were heterogeneous and rich in D-Mannose, D-Glucose and N-Acetyl-Glucosamine. The relationship between the appearance of 100kD γ-GT cluster and the heterogeneous carbohydrate components will be further studied.展开更多
文摘γ-Glutamyltranspeptidase (γ-GT) from human esophageal cancer, normal esophageal mucosa and normal kindney were partially purified and their biochemical and immunological properties were studied. (1) The γ-GT activity of esophageal cancer was higher than that of normal mucosa, yet still much lower than that of normal kidney. (2) The Michaelis constant and optimum pH of esophageal cancer γ-GT were the same as those of normal kidney tissue. (3) After staining of γ-GT activity, two molecular clusters, i.e. 100kD and 380kD γ-GT were shown in esophageal cancer by 4-20% linear gradient PAGE and the lOOkD γ-GT showed higher activity. (4) The γ-GT of esophageal cancer was immunologically identical with normal enzyme in double immunodif-fusion and immunoelectrophoresis. (5) In double lectin-diffusion, affinity column and crossed immuno-affino-electrophoresis, it was demonstrated that the carbohydrate components of γ-GT from esophageal cancer were heterogeneous and rich in D-Mannose, D-Glucose and N-Acetyl-Glucosamine. The relationship between the appearance of 100kD γ-GT cluster and the heterogeneous carbohydrate components will be further studied.