| Effect of 2-chloroethylnitrosoureas on plasmid DNA including formation of strand breaks and interstrand cross-links. | |
| | |
MedLine Citation:
|
PMID: 6311446 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Plasmid [3H]pBR 322 was incubated with various alkylating agents including chlorozotocin, N,N'-bis(2-chloroethyl)-N'-nitrosourea (BCNU), N-ethyl-N-nitrosourea (Enu) and dimethylsulfate (DMS). Formation of DNA strand breaks was followed by separation of the various forms of DNA on agarose gels and liquid scintillation counting of the bands. All alkylating agents examined were capable of rapidly producing strand breaks in time and concentration dependent fashion. Bands migrating as relaxed circular and supercoiled forms of the plasmid disappeared, and extensive alkylation resulted in formation of a band that migrated faster than the linear form of DNA. Electron microscopy of this band showed that it consisted of relaxed circles. Prolonged storage of alkylated plasmid resulted in fragmentation of the DNA, possibly due to strand scission at apurinic sites. A new neutral denaturation technique was developed, which allowed for the detection of DNA interstrand cross-links with minimal effects on other potentially labile sites of the alkylated DNA. The level of alkylation was quantitated by incubating [3H]pBR 322 with [2-chloroethyl-U-14C]chlorozotocin and was shown to be independent of DNA concentration but have a linear relationship with drug concentration. Linear and relaxed circular forms of the plasmid were alkylated to a somewhat higher extent than supercoiled DNA. Alkylation of pBR 322 with defined superhelical densities showed no preferential loss in DNA with a specific superhelical density, indicating that alkylation-induced unwinding is independent of superhelicity under the experimental conditions used. |
| | |
Authors:
|
H V Vadi; D J Reed |
Related Documents
:
|
23395936 - Association between gstm1 polymorphism and dna adduct concentration in the occupational... 17947076 - Imaging cross-section of dna electrophoresis in a microfabricated glass device with clsm. 7199396 - The significance of dna cross-linking to cis-diamminedichloroplatinum(ii)-induced cytot... 23368416 - Cisplatin enhances the formation of dna single- and double-strand breaks by hydrated el... 11271296 - Comparison of serological and dna hla-dr typing results for transplantation in western ... 23395936 - Association between gstm1 polymorphism and dna adduct concentration in the occupational... |
Publication Detail:
|
Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
|
Title: Chemico-biological interactions Volume: 46 ISSN: 0009-2797 ISO Abbreviation: Chem. Biol. Interact. Publication Date: 1983 Aug |
Date Detail:
|
Created Date: 1983-11-23 Completed Date: 1983-11-23 Revised Date: 2007-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 0227276 Medline TA: Chem Biol Interact Country: NETHERLANDS |
Other Details:
|
Languages: eng Pagination: 67-84 Citation Subset: IM |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Alkylation Carmustine / toxicity DNA Replication / drug effects DNA Restriction Enzymes DNA, Bacterial / genetics*, isolation & purification Escherichia coli / genetics Kinetics Microscopy, Electron Mutagens / toxicity* Nitrogen Mustard Compounds / toxicity* Nitrosourea Compounds / toxicity* Plasmids / drug effects* |
| Grant Support | |
ID/Acronym/Agency:
|
CA 25561/CA/NCI NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/DNA, Bacterial; 0/Mutagens; 0/Nitrogen Mustard Compounds; 0/Nitrosourea Compounds; 154-93-8/Carmustine; EC 3.1.21.-/DNA Restriction Enzymes |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Comparison of cytochrome P-450-dependent metabolism in different developmental stages of Drosophila ...
Next Document: Effect of dietary butylated hydroxyanisole on the mouse hepatic monooxygenase system of nuclear and ...