TOPOISOMERASE-I IN ACTIVELY GROWING PLASMODIA AND DURING DIFFERENTIATION OF THE SLIME-MOLD PHYSARUM-POLYCEPHALUM

被引：6

作者：

STARON, K

KOWALSKALOTH, B

CZERWINSKI, RM

BANDOROWSKA, J

GUBERSKA, J

机构：

[1] Department of Biochemistry, Warsaw University, Warszawa

来源：

BIOCHIMICA ET BIOPHYSICA ACTA | 1991年 / 1088卷 / 01期

关键词：

DNA TOPOISOMERASE-I; ENZYME PURIFICATION; SPHERULATION; (P-POLYCEPHALUM);

D O I：

10.1016/0167-4781(91)90150-K

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

A type I topoisomerase has been purified from nuclei of a slime mold Physarum polycephalum and its activity was tested during spherulation. The final preparation contained a single polypeptide of about 100 kDa. Basic properties of Physarum topoisomerase I (substrate specificity, ionic requirement, sensitivity to inhibitors) were similar to those of topoisomerases from higher eukaryotes. Specific features of Physarum enzyme were that it was rapidly inactivated at 45-degrees-C and did not react with antibodies against human topoisomerase I. The activity of topoisomerase I in developed dormant spherules decreased approx. 2-fold, as compared with a 4-fold decrease of RNA and a 10-fold decrease of DNA synthesis. Basic properties of the enzyme remained unchanged during spherulation.

引用

页码：36 / 40

页数：5

共 36 条

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