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. 1986 Jan;83(2):394–398. doi: 10.1073/pnas.83.2.394

Gene control in broad host range plasmid RK2: expression, polypeptide product, and multiple regulatory functions of korB.

D H Bechhofer, J A Kornacki, W Firshein, D H Figurski
PMCID: PMC322865  PMID: 3455777

Abstract

The korB gene of broad host-range plasmid RK2 prevents host-cell lethality by kilB and negatively controls RK2 replication. We precisely mapped the limits of korB to a region near korA, an autoregulated gene involved in control of several RK2 genes. The following results show that korA and korB are cotranscribed from the korA promoter: Mutants deleted for the korA promoter fail to express korB, even with korA function supplied in trans; the korA promoter is nonessential to korB if a heterologous promoter is present; and RNA produced in vivo has both korA- and korB-specific sequences. Analysis of polypeptides synthesized from wild-type and mutant korB plasmids in maxicells revealed that korB encodes a 52-kDa polypeptide, whose activity is extremely sensitive to changes in its carboxyl terminus but relatively unaffected by replacement of its amino terminus. The minimal korB-encoding region allowed us to identify two new regulatory functions, both of which duplicate previously known functions of korA. First, korB alone was found to control the kilB1 component of kilB, thus resolving the paradox of korA-independent control of kilB. Second, analysis of polypeptides from the korA-korB region in the presence and absence of korB, and studies with the korA promoter fused to the chloramphenicol acetyltransferase structural gene (cat) showed that korB, like korA, autoregulates expression of the korA-korB operon. We suggest that korA and korB gene products act as co-repressors in the control of certain RK2 genes.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Barth P. T., Ellis K., Bechhofer D. H., Figurski D. H. Involvement of kil and kor genes in the phenotype of a host-range mutant of RP4. Mol Gen Genet. 1984;197(2):236–243. doi: 10.1007/BF00330969. [DOI] [PubMed] [Google Scholar]
  2. Bechhofer D. H., Figurski D. H. Map location and nucleotide sequence of korA, a key regulatory gene of promiscuous plasmid RK2. Nucleic Acids Res. 1983 Nov 11;11(21):7453–7469. doi: 10.1093/nar/11.21.7453. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bolivar F., Rodriguez R. L., Greene P. J., Betlach M. C., Heyneker H. L., Boyer H. W., Crosa J. H., Falkow S. Construction and characterization of new cloning vehicles. II. A multipurpose cloning system. Gene. 1977;2(2):95–113. [PubMed] [Google Scholar]
  4. Chang A. C., Cohen S. N. Construction and characterization of amplifiable multicopy DNA cloning vehicles derived from the P15A cryptic miniplasmid. J Bacteriol. 1978 Jun;134(3):1141–1156. doi: 10.1128/jb.134.3.1141-1156.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Chang A. C., Cohen S. N. Construction and characterization of amplifiable multicopy DNA cloning vehicles derived from the P15A cryptic miniplasmid. J Bacteriol. 1978 Jun;134(3):1141–1156. doi: 10.1128/jb.134.3.1141-1156.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Close T. J., Rodriguez R. L. Construction and characterization of the chloramphenicol-resistance gene cartridge: a new approach to the transcriptional mapping of extrachromosomal elements. Gene. 1982 Dec;20(2):305–316. doi: 10.1016/0378-1119(82)90048-8. [DOI] [PubMed] [Google Scholar]
  7. Datta N., Hedges R. W. Host ranges of R factors. J Gen Microbiol. 1972 May;70(3):453–460. doi: 10.1099/00221287-70-3-453. [DOI] [PubMed] [Google Scholar]
  8. Derman E., Krauter K., Walling L., Weinberger C., Ray M., Darnell J. E., Jr Transcriptional control in the production of liver-specific mRNAs. Cell. 1981 Mar;23(3):731–739. doi: 10.1016/0092-8674(81)90436-0. [DOI] [PubMed] [Google Scholar]
  9. Figurski D. H., Helinski D. R. Replication of an origin-containing derivative of plasmid RK2 dependent on a plasmid function provided in trans. Proc Natl Acad Sci U S A. 1979 Apr;76(4):1648–1652. doi: 10.1073/pnas.76.4.1648. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Figurski D. H., Pohlman R. F., Bechhofer D. H., Prince A. S., Kelton C. A. Broad host range plasmid RK2 encodes multiple kil genes potentially lethal to Escherichia coli host cells. Proc Natl Acad Sci U S A. 1982 Mar;79(6):1935–1939. doi: 10.1073/pnas.79.6.1935. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Heffron F., McCarthy B. J., Ohtsubo H., Ohtsubo E. DNA sequence analysis of the transposon Tn3: three genes and three sites involved in transposition of Tn3. Cell. 1979 Dec;18(4):1153–1163. doi: 10.1016/0092-8674(79)90228-9. [DOI] [PubMed] [Google Scholar]
  12. Hershfield V., Boyer H. W., Yanofsky C., Lovett M. A., Helinski D. R. Plasmid ColEl as a molecular vehicle for cloning and amplification of DNA. Proc Natl Acad Sci U S A. 1974 Sep;71(9):3455–3459. doi: 10.1073/pnas.71.9.3455. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Ingram L. C., Richmond M. H., Sykes R. B. Molecular characterization of the R factors implicated in the carbenicillin resistance of a sequence of Pseudomonas aeruginosa strains isolated from burns. Antimicrob Agents Chemother. 1973 Feb;3(2):279–288. doi: 10.1128/aac.3.2.279. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Kahn M., Kolter R., Thomas C., Figurski D., Meyer R., Remaut E., Helinski D. R. Plasmid cloning vehicles derived from plasmids ColE1, F, R6K, and RK2. Methods Enzymol. 1979;68:268–280. doi: 10.1016/0076-6879(79)68019-9. [DOI] [PubMed] [Google Scholar]
  15. Kornacki J. A., West A. H., Firshein W. Proteins encoded by the trans-acting replication and maintenance regions of broad host range plasmid RK2. Plasmid. 1984 Jan;11(1):48–57. doi: 10.1016/0147-619x(84)90006-4. [DOI] [PubMed] [Google Scholar]
  16. Meyer R. J., Helinski D. R. Unidirectional replication of the P-group plasmid RK2. Biochim Biophys Acta. 1977 Sep 6;478(1):109–113. doi: 10.1016/0005-2787(77)90249-0. [DOI] [PubMed] [Google Scholar]
  17. Meyer R., Figurski D., Helinski D. R. Physical and genetic studies with restriction endonucleases on the broad host-range plasmid RK2. Mol Gen Genet. 1977 Apr 29;152(3):129–135. doi: 10.1007/BF00268809. [DOI] [PubMed] [Google Scholar]
  18. Meyer R., Hinds M. Multiple mechanisms for expression of incompatibility by broad-host-range plasmid RK2. J Bacteriol. 1982 Dec;152(3):1078–1090. doi: 10.1128/jb.152.3.1078-1090.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Oka A., Sugisaki H., Takanami M. Nucleotide sequence of the kanamycin resistance transposon Tn903. J Mol Biol. 1981 Apr 5;147(2):217–226. doi: 10.1016/0022-2836(81)90438-1. [DOI] [PubMed] [Google Scholar]
  20. Olsen R. H., Shipley P. Host range and properties of the Pseudomonas aeruginosa R factor R1822. J Bacteriol. 1973 Feb;113(2):772–780. doi: 10.1128/jb.113.2.772-780.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Pohlman R. F., Figurski D. H. Essential genes of plasmid RK2 in Escherichia coli: trfB region controls a kil gene near trfA. J Bacteriol. 1983 Nov;156(2):584–591. doi: 10.1128/jb.156.2.584-591.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Rigby P. W., Dieckmann M., Rhodes C., Berg P. Labeling deoxyribonucleic acid to high specific activity in vitro by nick translation with DNA polymerase I. J Mol Biol. 1977 Jun 15;113(1):237–251. doi: 10.1016/0022-2836(77)90052-3. [DOI] [PubMed] [Google Scholar]
  23. Sancar A., Hack A. M., Rupp W. D. Simple method for identification of plasmid-coded proteins. J Bacteriol. 1979 Jan;137(1):692–693. doi: 10.1128/jb.137.1.692-693.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Schmidhauser T. J., Filutowicz M., Helinski D. R. Replication of derivatives of the broad host range plasmid RK2 in two distantly related bacteria. Plasmid. 1983 May;9(3):325–330. doi: 10.1016/0147-619x(83)90010-0. [DOI] [PubMed] [Google Scholar]
  25. Schmidhauser T. J., Helinski D. R. Regions of broad-host-range plasmid RK2 involved in replication and stable maintenance in nine species of gram-negative bacteria. J Bacteriol. 1985 Oct;164(1):446–455. doi: 10.1128/jb.164.1.446-455.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Schreiner H. C., Bechhofer D. H., Pohlman R. F., Young C., Borden P. A., Figurski D. H. Replication control in promiscuous plasmid RK2: kil and kor functions affect expression of the essential replication gene trfA. J Bacteriol. 1985 Jul;163(1):228–237. doi: 10.1128/jb.163.1.228-237.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Shinger V., Thomas C. M. Transcription in the trfA region of broad host range plasmid RK2 is regulated by trfB and korB. Mol Gen Genet. 1984;195(3):523–529. doi: 10.1007/BF00341457. [DOI] [PubMed] [Google Scholar]
  28. Shingler V., Thomas C. M. Analysis of the trfA region of broad host-range plasmid RK2 by transposon mutagenesis and identification of polypeptide products. J Mol Biol. 1984 May 25;175(3):229–249. doi: 10.1016/0022-2836(84)90346-2. [DOI] [PubMed] [Google Scholar]
  29. Smith C. A., Shingler V., Thomas C. M. The trfA and trfB promoter regions of broad host range plasmid RK2 share common potential regulatory sequences. Nucleic Acids Res. 1984 Apr 25;12(8):3619–3630. doi: 10.1093/nar/12.8.3619. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Smith C. A., Thomas C. M. Molecular gentic analysis of the trfB and korB region of broad host range plasmid RK2. J Gen Microbiol. 1984 Jul;130(7):1651–1663. doi: 10.1099/00221287-130-7-1651. [DOI] [PubMed] [Google Scholar]
  31. Smith C. A., Thomas C. M. Nucleotide sequence of the trfA gene of broad host-range plasmid RK2. J Mol Biol. 1984 May 25;175(3):251–262. doi: 10.1016/0022-2836(84)90347-4. [DOI] [PubMed] [Google Scholar]
  32. Stalker D. M., Thomas C. M., Helinski D. R. Nucleotide sequence of the region of the origin of replication of the broad host range plasmid RK2. Mol Gen Genet. 1981;181(1):8–12. doi: 10.1007/BF00338997. [DOI] [PubMed] [Google Scholar]
  33. Thomas C. M. Complementation analysis of replication and maintenance functions of broad host range plasmids RK2 and RP1. Plasmid. 1981 May;5(3):277–291. doi: 10.1016/0147-619x(81)90005-6. [DOI] [PubMed] [Google Scholar]
  34. Thomas C. M., Hussain A. A., Smith C. A. Maintenance of broad host range plasmid RK2 replicons in Pseudomonas aeruginosa. Nature. 1982 Aug 12;298(5875):674–676. doi: 10.1038/298674a0. [DOI] [PubMed] [Google Scholar]
  35. Thomas C. M., Hussain A. A. The korB gene of broad host range plasmid RK2 is a major copy number control element which may act together with trfB by limiting trfA expression. EMBO J. 1984 Jul;3(7):1513–1519. doi: 10.1002/j.1460-2075.1984.tb02004.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Thomas C. M., Meyer R., Helinski D. R. Regions of broad-host-range plasmid RK2 which are essential for replication and maintenance. J Bacteriol. 1980 Jan;141(1):213–222. doi: 10.1128/jb.141.1.213-222.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Thomas C. M., Stalker D. M., Helinski D. R. Replication and incompatibility properties of segments of the origin region of replication of the broad host range plasmid RK2. Mol Gen Genet. 1981;181(1):1–7. doi: 10.1007/BF00338996. [DOI] [PubMed] [Google Scholar]
  38. Thomas P. S. Hybridization of denatured RNA and small DNA fragments transferred to nitrocellulose. Proc Natl Acad Sci U S A. 1980 Sep;77(9):5201–5205. doi: 10.1073/pnas.77.9.5201. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Young C., Bechhofer D. H., Figurski D. H. Gene regulation in plasmid RK2: positive control by korA in the expression of korC. J Bacteriol. 1984 Jan;157(1):247–252. doi: 10.1128/jb.157.1.247-252.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Young C., Prince A. S., Figurski D. H. korA function of promiscuous plasmid RK2: an autorepressor that inhibits expression of host-lethal gene kilA and replication gene trfA. Proc Natl Acad Sci U S A. 1985 Nov;82(21):7374–7378. doi: 10.1073/pnas.82.21.7374. [DOI] [PMC free article] [PubMed] [Google Scholar]

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