The Influence of Antibiotics and Antitumor Agents on the Relaxation Activity of Pisum sativum Leaf Chloroplast Topoisomerase I

DNA topoisomerase was isolated from pea leaf chloroplasts. The relaxation activity of this topoisomerase was Mg2+ dependent and sensitive to ethidium bromide and novobiocin, a gyrase inhibitor. Chloroplast topoisomerase (Topo I) was ATP independent, as shown by the characteristic gel distribution of...

Full description

Saved in:
Bibliographic Details
Published in:Archives of biochemistry and biophysics 1995-06, Vol.320 (1), p.177-181
Main Authors: Zagariya, A.M., Sitailo, L.A.
Format: Article
Language:English
Subjects:
activador enzimatico
activateur d' enzyme
actividad enzimatica
activite enzymatique
adn
Amiloride - pharmacology
Amsacrine - pharmacology
Anti-Bacterial Agents - pharmacology
antibioticos
antibiotics
antibiotique
Antineoplastic Agents - pharmacology
Camptothecin - pharmacology
chloroplaste
chloroplasts
Chloroplasts - enzymology
cloroplasto
dna
DNA Topoisomerases, Type I - metabolism
DNA, Plant - drug effects
DNA, Plant - metabolism
enzimas
enzyme
enzyme activators
enzyme inhibitors
enzymes
enzymic activity
Ethidium - pharmacology
feuille
Heparin - pharmacology
hojas
Indoles - pharmacology
inhibidores de enzimas
inhibiteur d' enzyme
leaves
Magnesium - pharmacology
Nalidixic Acid - pharmacology
Novobiocin - pharmacology
pisum sativum
Pisum sativum - enzymology
Polyamines - pharmacology
Topoisomerase I Inhibitors
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:DNA topoisomerase was isolated from pea leaf chloroplasts. The relaxation activity of this topoisomerase was Mg2+ dependent and sensitive to ethidium bromide and novobiocin, a gyrase inhibitor. Chloroplast topoisomerase (Topo I) was ATP independent, as shown by the characteristic gel distribution of topoisomers. Topoisomerase, compared with the known eucaryotic topoisomerase I, was not stimulated by polyamines as are spermidine, spermine, and cadaverine. Ethidium bromide, DAPI, heparin, nalidixic acid, and m-AMSA (but not camptothecin) were able to inhibit the relaxation activity of chloroplast topo I. Nalidixic acid, novobiocin, m-AMSA, camptothecin, and amiloride were tested for their effects on the topo-isomerase-catalyzed "cleavage complex" between DNA and chloroplast DNA topoisomerase I.
ISSN:0003-9861
1096-0384
DOI:10.1006/abbi.1995.1357