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SUPERCOILED CIRCULAR DNA-PROTEIN COMPLEX IN Escherichia coli : PURIFICATION AND INDUCED CONVERSION TO AN OPEN CIRCULAR DNA FORM
Open accessAbstract
The 23 S twisted circular form of Col E 1 DNA has been isolated from Escherichia coli as a tightly associated DNA-protein complex with a sedimentation coefficient of approximately 24 S . Treatment of this complex with pronase, trypsin, sodium dodecyl sulfate, Sarkosyl, or heat results in a conversion to a slower sedimenting form of 17 S or 18 S , as determined by centrifugation in neutral sucrose gradients. These treatments do not alter the sedimentation properties of noncomplexes supercoiled Col E 1 DNA even in the presence of the Col E 1 -protein complex. Electron microscopic analyses indicate that the decrease in sedimentation rate of the Col E 1 -protein complex after treatment with these various agents is largely owing to an induced transition of Col E 1 DNA from the supercoiled to the open circular state.
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Citations
Cited by
A rapid alkaline extraction procedure for screening recombinant plasmid DNA
Birnboim, H. C., & Doly, J. (1979) · Nucleic Acids Research · doi:10.1093/nar/7.6.1513 · Cited by 14,686
Rushmore, T. H., Morton, M. R., & Pickett, C. B. (1991) · Journal of Biological Chemistry · doi:10.1016/s0021-9258(18)99004-6 · Cited by 1,464
Transformation of yeast by a replicating hybrid plasmid
Beggs, J. D. (1978) · Nature · doi:10.1038/275104a0 · Cited by 1,316
Ross, J. I., Eady, E. A., Cove, J. H., Cunliffe, W. J., Baumberg, S., & Wootton, J. C. (1990) · Molecular Microbiology · doi:10.1111/j.1365-2958.1990.tb00696.x · Cited by 358
A classification scheme for mobilization regions of bacterial plasmids
Francia, M. V., Varsaki, A., Garcillán-Barcia, M. P., Latorre, A., Drainas, C., & de la Cruz, F. (2004) · FEMS Microbiology Reviews · doi:10.1016/j.femsre.2003.09.001 · Cited by 359
Metadata
- Authors
- Clewell, D. B., & Helinski, D. R.
- Venue
- Proceedings of the National Academy of Sciences
- Published
- 1969-04
- Volume
- 62
- Issue
- 4
- Pages
- 1159-1166
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- OpenAlex
- W2001918964
- Cited by
- 1,820
- References
- 0
- FWCI
- 8.94
- Type
- journal article
- Language
- en
- Open access
- green
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- CoChat. (2026). Citation check: SUPERCOILED CIRCULAR DNA-PROTEIN COMPLEX IN Escherichia coli : PURIFICATION AND INDUCED CONVERSION TO AN OPEN CIRCULAR DNA FORM. https://app.cochat.ai/papers/10.1073/pnas.62.4.1159
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- Clewell, D. B., & Helinski, D. R. (1969). SUPERCOILED CIRCULAR DNA-PROTEIN COMPLEX IN Escherichia coli : PURIFICATION AND INDUCED CONVERSION TO AN OPEN CIRCULAR DNA FORM. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.62.4.1159
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
