Novel triterpenoids inhibit both DNA polymerase and DNA topoisomerase
نویسندگان
چکیده
منابع مشابه
Flavonoids in Helichrysum pamphylicum inhibit mammalian type I DNA topoisomerase.
DNA topoisomerases are important targets for cancer chemotherapy. We investigated the effects of a methanolic extract of Helichrysum pamphylicum on mammalian DNA topoisomerase I via in vitro plasmid supercoil relaxation assays. The extracts manifested a considerable inhibition of the enzyme's activity in a dose-dependent manner. We also performed a HPLC analysis to identify the flavonoid conten...
متن کاملRecQ helicase stimulates both DNA catenation and changes in DNA topology by topoisomerase III.
Together, RecQ helicase and topoisomerase III (Topo III) of Escherichia coli comprise a potent DNA strand passage activity that can catenate covalently closed DNA (Harmon, F. G., DiGate, R. J., and Kowalczykowski, S. C. (1999) Mol. Cell 3, 611-620). Here we directly assessed the structure of the catenated DNA species formed by RecQ helicase and Topo III using atomic force microscopy. The images...
متن کاملEvodiamine stabilizes topoisomerase I-DNA cleavable complex to inhibit topoisomerase I activity.
Evodiamine (EVO), an alkaloidal compound isolated from Evodia rutaecarpa (Juss.), has been reported to affect many physiological functions. Topoisomerase inhibitors have been developed in a variety of clinical applications. In the present study, we report the topoisomerase I (TopI) inhibitory activity of EVO, which may have properties that lead to improved therapeutic benefits. EVO is able to i...
متن کاملCleavage of DNA by Mammalian DNA Topoisomerase
Using the P4 unknotting assay, DNA topoisomerase I1 has been purified from several mammalian cells. Similar to prokaryotic DNA gyrase, mammalian DNA topoisomerase I1 can cleave double-stranded DNA and be trapped as a covalent protein-DNA complex. This cleavage reaction requires protein denaturant treatment of the topoisomerse 11-DNA complex and is reversible with respect to salt and temperature...
متن کاملRNA aptamers selected against DNA polymerase β inhibit the polymerase activities of DNA polymerases β and κ
DNA polymerase beta (polbeta), a member of the X family of DNA polymerases, is the major polymerase in the base excision repair pathway. Using in vitro selection, we obtained RNA aptamers for polbeta from a variable pool of 8 x 10(12) individual RNA sequences containing 30 random nucleotides. A total of 60 individual clones selected after seven rounds were screened for the ability to inhibit po...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biochemical Journal
سال: 2000
ISSN: 0264-6021,1470-8728
DOI: 10.1042/bj3500757