Summary
PT181 is a fully sequenced Staphylococcus aureus plasmid whose size is 4,437 bp. It specifies tetracycline resistance and has a copy number of about 22 per cell in exponentially growing cultures. The functional organization of the pT181 replicon is centered around the coding sequence for a 35-kd protein, RepC, that is absolutely required for replication of the plasmid. The replication origin is contained within the repC coding sequence and the region immediately 5f to the RepC start is involved in control of the plasmid replication rate. PT181 replication is controlled at the level of RepC synthesis by a negative regulatory system that is functionally similar to that of the Co1E1 and IncFII plasmids ofEscherichia coli. The pT181 control circuit involves 2 short transcripts, RNA I and RNA II, that are transcribed from the region specifying the 5’ end of the untranslated repC mRNA leader and in the opposite direction. These are referred to as countertranscripts. The countertranscripts regulate RepC synthesis by a mechanism that probably involves interaction with the repC mRNA leader in a manner that interferes with translation. Both of the countertranscripts seem to be necessary for normal replication control; their separate roles remain unclear.
Unlike plasmids of the ColEl and IncFII groups, plasmids such as ColEl are considered to have direct regulation of replication because the inhibitory element of the copy control circuit directly inhibits the initiation of replication. Plasmids such as pT181 are considered to have indirect regulation of replication because the product of the regulated step, RepC, is trans-active.
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References
Grindley, N.D.F., J.N. Grindley, and W.S. Kelley (1978) Mutant plasmid with altered replication control. InMicrobiology—1978, D. Schlessinger, ed. Am. Soc. Microbiol., Washington, D.C., pp. 71–73.
Khan, S.A., and R.P. Novick (1983) Complete nucleotide sequence of pT181, a tetracycline resistance plasmid fromstaphylococcus aureus.Plasmid 10:251–259.
Novick, R.P., G.K. Adler, S. Majumder, S.A. Khan, S. Carleton, W. Rosenblum, and S. Iordanescu (1982) Coding sequence for the pT181repC product: A plasmid-coded protein uniquely required for replication.Proc. Natl. Acad. Sci., USA 79:4108–4112.
Khan, S., S. Carleton, and R.P Novick (1981) Replication of plasmid pT181 DNAin vitro: Requirement for a plasmid coded product.Proc. Natl. Acad. Sci., USA 78:4902–4906.
Khan, S.A., G.K. Adler, and R.P. Novick (1982) Functional origin of replication of pT181 plasmid DNA is contained within a 168-base-pair segment.Proc. Natl. Acad. Sci., USA 79:4580–4584.
Kumar, C., and R.P. Novick (1984) Plasmid pT181 replication is regulated by two countertranscripts. Submitted toProc. Natl. Acad. Sci., USA.
Novick, R.P,, G.K. Adler, S.J. Projan, S. Carleton, S.K. Highlander, A. Gruss, S.A. Khan, and S. Iordanescu (1984) Control of pT181 Replication I. The pT181 copy control function acts by inhibiting the synthesis of a replication protein. Submitted toEmbo J.
Carleton S., S.J. Projan, S.K. Highland, S.M. Moghazeh, and R.P. Novick (1984) Control of pT181 Replication II. Mutational analysis. Submitted toEmbo J.
Eckhardt, T. (1978) A rapid method for the identification of plasmid deoxyribonucleic acid in bacteria.Plasmid 1:584–588.
Projan, S.J., S. Carleton, and R.P. Novick (1983) Determination of plasmid copy number by fluorescence densitometry.Plasmid 9:182–190.
Lacatena, R.M., and G. Cesareni (1981) Base pairing of RNA I with its complementary sequence in the primer precursor inhibits ColE1 replication.Nature 294:623–626.
Lacatena, R.M., and G. Cesareni (1983) Anatomy of the target of the inhibitor of ColE1 replication. InAbstracts of the 1982 EMBO Conference, “Replication of Prokaryotic DNA,” The Netherlands, pp.62–65.
Tomizawa, J.-I., and T. Itoh (1981) Plasmid ColE1 incompatibility determined by interaction of RNA I with primer transcript.Proc. Natl. Acad. Sci., USA 78:6096–6100.
Brady, G., J. Frey, H. Danbara, and K. Timmis (1983) Replication control mutations of plasmid R6-5 and their consequences for interactions of the RNA-I control element with its target.J. Bact. 154:429–436.
Nordstrom, K., S. Molin, and H. Aagaard-Hansen (1981) Plasmid Rl incompatibility. InMolecular Biology, Pathogenicity, and Ecology of Bacterial Plasmids, R.C. Clowes, S.B. Levy, and E.L. Koening, eds. Plenum Press, New York, pp. 291–301.
Zuker, M., and P. Stiegler (1981) Optimal computer folding of large RNA sequences using thermodynamics and auxiliary information.Nucleic Acids Res. 9:133–148.
Tomizawa, J.-I., and T. Itoh (1982) The importance of RNA secondary structure in ColE1 primer formation.Cell 31:575–583.
Pritchard, R.H., P.B. Barth, and J. Collins (1969) Control of DNA synthesis in bacteria.Symp. Soc. Gen. Microb. 19:263–297.
Novick, R.P., and F. Hoppensteadt (1978) On plasmid incompatibility.Plasmid 1:421–434.
Projan, S.J., and R.P. Novick (1984) Reciprocal intrapool variation in plasmid copy numbers: A characteristic of segregational incompatibility. Plasmid (in press).
Easton, A.M., and R.H. Rownd (1982) The incompatibility product of IncFII R plasmid NR1 controls gene expression in the plasmid replication region. J. Bact. 152:829–839.
Horinouchi, S., and B. Weisblum (1982) Nucleotide sequence and functional map of pE194, a plasmid that specifies inducible resistance to macrolide, linosamide and streptogramin type B antibiotics. J. Bact. 150:815–825.
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© 1985 Plenum Press, New York
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Novick, R.P. et al. (1985). Replication Control for PT181, an Indirectly Regulated Plasmid. In: Helinski, D.R., Cohen, S.N., Clewell, D.B., Jackson, D.A., Hollaender, A. (eds) Plasmids in Bacteria. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-2447-8_24
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