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Lack of Z-DNA conformation in mitomycin-modified polynucleotides having inverted circular dichroism.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Tomasz, M. Karpiński Barton, Jacqueline K. Magliozzo, C. C. Tucker, Douglas Lafer, Eileen M. Stollar, B. David |
| Copyright Year | 1983 |
| Abstract | Poly(dG-dC) . poly(dG-dC) and Micrococcus lysodeikticus DNA were modified by exposure to reductively activated mitomycin C, an antitumor antibiotic. The resulting covalent drug-polynucleotide complexes displayed varying degrees of CD inversions, which are strikingly similar to the inverted spectrum observed with Z-DNA. The following criteria have been used to establish, however, that the inverted CD pattern seen in mitomycin C-polynucleotide complexes does not reflect a Z-DNA conformation. (i) The ethanol-induced transition of poly(dG-dC) . poly(dG-dC) from B to Z conformation is not facilitated but rather is inhibited by mitomycin C modification. This may be due to the presence of crosslinks, (ii) Radioimmunoassay indicated no competition for Z-DNA-specific antibody by any of the mitomycin C-modified polynucleotides, (iii) 31P NMR of the complexes yielded a single relatively narrow resonance, which is inconsistent with the dinucleotide repeat characteristic of Z-DNA. Alternative explanations for the inverted CD pattern include a drug-induced left-handed but non-Z conformational change or the superposition of an induced CD onto the CD of B-DNA due to drug-base electronic interactions. These results illustrate the need for caution in interpreting CD changes alone as an indication of Z-DNA conformation. |
| File Format | PDF HTM / HTML |
| DOI | 10.1073/pnas.80.10.2874 |
| PubMed reference number | 6574457 |
| Journal | Medline |
| Volume Number | 80 |
| Issue Number | 10 |
| Alternate Webpage(s) | http://authors.library.caltech.edu/668/1/TOMpnas83.pnas.pdf |
| Alternate Webpage(s) | https://doi.org/10.1073/pnas.80.10.2874 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
