大鼠肝癌的UDP-N-乙酰葡糖胺2'-表异构酶及其与大鼠肝脏该酶的比较。

UDP-N-acetylglucosamine 2'-epimerase of rat hepatoma and its comparison with the enzyme of rat liver.

作者信息

Kikuchi K, Tsuiki S

出版信息

Tohoku J Exp Med. 1980 Jul;131(3):209-14. doi: 10.1620/tjem.131.209.

DOI:10.1620/tjem.131.209

Abstract

UDP-N-acetylglucosamine 2'-epimerase was partially purified from Yoshida sarcoma, a strain of rat ascites hepatoma, by (NH4)2SO4 precipitation followed by TEAE-cellulose chromatography. The purified enzyme was inhibited by CMP-N-acetylneuraminic acid to similar extent to partially purified rat liver 2'-epimerase. Although the two enzymes were also similar in Km for UDP-N-acetylglucosamine, they were differentiated by chromatography on TEAE-cellulose, DEAE-Sephadex and hydroxyapatite, tumor enzyme being less tightly bound to these columns than liver enzyme. Similar chromatographic difference was also noted between 2'-epimerases of mouse liver and mouse Ehrlich asites carcinoma.

摘要

通过硫酸铵沉淀，随后进行TEAE - 纤维素柱色谱法，从吉田肉瘤（一种大鼠腹水肝癌株）中部分纯化出UDP - N - 乙酰葡糖胺2'-表异构酶。纯化后的酶被CMP - N - 乙酰神经氨酸抑制的程度与部分纯化的大鼠肝脏2'-表异构酶相似。尽管这两种酶对UDP - N - 乙酰葡糖胺的米氏常数也相似，但通过TEAE - 纤维素、DEAE - 葡聚糖凝胶和羟基磷灰石柱色谱法可将它们区分开来，肿瘤酶与这些柱的结合比肝脏酶弱。在小鼠肝脏和小鼠艾氏腹水癌的2'-表异构酶之间也观察到类似的色谱差异。