This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Bao-Shu, T. Articles by Xu, X.-L. Search for Related Content Social Bookmarking                         What's this?

"Pyran Copolymers" Inhibition of DNA Topoisomerase I from Human Spleen

Department of Biology Yunnan College of Education Kunming, P.R. of China

Li-Kei Wang

Department of Biochemistry Sun Yat-Sen University of Medical Science Guangzhou, P.R. of China

Xiao-Li Xu

Department of Biochemistry Sun Yat-Sen University of Medical Science Guangzhou, P.R. of China

"Pyran copolymers" (DIVEMA, FMA and FMAHA), a category of known synthetic polyanions, were found to be potent inhibitors of purified DNA topoisomerase I from human spleen in vitro. DIVEMA, FMA and FMAHA com pletely inhibit the relaxing activity of the topoisomerase I at concentrations of 0.09, 0.6 and 0.5 µg/ml, respectively. The inhibition is reversible. When the substrate (supercoiled plamid PBR322 DNA) and the enzyme are increased to 2 or 3 fold of the initial amount the inhibition is partly overcome. The inhibi tion is specific; they do not inhibit the uncoupling activity of DNA topoiso merase II at a concentration of 100 µg/ml, nor do they inhibit the digesting ac tivity of DNase I at a concentration of 1000 µg/ml.

Journal of Bioactive and Compatible Polymers, Vol. 5, No. 1, 65-79 (1990)
DOI: 10.1177/088391159000500107


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?