Logo of jbacterPermissionsJournals.ASM.orgJournalJB ArticleJournal InfoAuthorsReviewers
J Bacteriol. 1984 Jan; 157(1): 247–252.
PMCID: PMC215159

Gene regulation in plasmid RK2: positive control by korA in the expression of korC.


The broad-host-range plasmid RK2 encodes three host-lethal kil genes whose actions are controlled by specific kor genes. We have shown previously that the 0' to 5.5' region of RK2 encodes both kilA and korC. Because of the lethal effect of kilA, plasmids with this region cannot be maintained in Escherichia coli unless the RK2 korA gene is also present. To investigate korC in the absence of kilA and therefore of korA, we first mapped kilA and korC to specific segments of the cloned 0' to 5.5' region. This allowed us to construct a korC+ plasmid missing the kilA region and thereby removed the need to have korA in the cell. We found that this korC-encoding plasmid alone is insufficient to control kilC. The korA function is required, and it can be supplied in trans. We also constructed a kilA+ korC- plasmid and found that korA is sufficient to control kilA. Thus, in addition to acting negatively to control kilA, korA acts positively to allow korC control of kilC. This korA dependence of korC is bypassed in a rho-115 mutant of E. coli. We consider the possibility that korA product acts as an antiterminator of transcription in korC expression.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.0M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Alton NK, Vapnek D. Nucleotide sequence analysis of the chloramphenicol resistance transposon Tn9. Nature. 1979 Dec 20;282(5741):864–869. [PubMed]
  • Bachmann BJ. Pedigrees of some mutant strains of Escherichia coli K-12. Bacteriol Rev. 1972 Dec;36(4):525–557. [PMC free article] [PubMed]
  • Blattner FR, Dahlberg JE. RNA synthesis startpoints in bacteriophage lambda: are the promoter and operator transcribed? Nat New Biol. 1972 Jun 21;237(77):227–232. [PubMed]
  • Burkardt HJ, Riess G, Pühler A. Relationship of group P1 plasmids revealed by heteroduplex experiments: RP1, RP4, R68 and RK2 are identical. J Gen Microbiol. 1979 Oct;114(2):341–348. [PubMed]
  • Cohen SN, Chang AC, Hsu L. Nonchromosomal antibiotic resistance in bacteria: genetic transformation of Escherichia coli by R-factor DNA. Proc Natl Acad Sci U S A. 1972 Aug;69(8):2110–2114. [PMC free article] [PubMed]
  • Cowan P, Krishnapillai V. Tn7 insertion mutations affecting the host range of the promiscuous IncP-1 plasmid R18. Plasmid. 1982 Sep;8(2):164–174. [PubMed]
  • Datta N, Hedges RW. Host ranges of R factors. J Gen Microbiol. 1972 May;70(3):453–460. [PubMed]
  • Dobritsa AP, Ivanova ZA, Fedoseeva VB. Transposition of DNA fragments flanked by two inverted Tn1 sequences: translocation of the plasmid RP4::Tn1 region harboring the Tcr marker. Gene. 1983 May-Jun;22(2-3):237–243. [PubMed]
  • Fiandt M, Szybalski W, Malamy MH. Polar mutations in lac, gal and phage lambda consist of a few IS-DNA sequences inserted with either orientation. Mol Gen Genet. 1972;119(3):223–231. [PubMed]
  • Figurski DH, Helinski DR. 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. [PMC free article] [PubMed]
  • Figurski DH, Pohlman RF, Bechhofer DH, Prince AS, Kelton CA. 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. [PMC free article] [PubMed]
  • Forbes D, Herskowitz I. Polarity suppression by the Q gene product of bacteriophage lambda. J Mol Biol. 1982 Oct 5;160(4):549–569. [PubMed]
  • Gottesman ME, Adhya S, Das A. Transcription antitermination by bacteriophage lambda N gene product. J Mol Biol. 1980 Jun 15;140(1):57–75. [PubMed]
  • Gottesman M, Oppenheim A, Court D. Retroregulation: control of gene expression from sites distal to the gene. Cell. 1982 Jul;29(3):727–728. [PubMed]
  • Guarneros G, Montañez C, Hernandez T, Court D. Posttranscriptional control of bacteriophage lambda gene expression from a site distal to the gene. Proc Natl Acad Sci U S A. 1982 Jan;79(2):238–242. [PMC free article] [PubMed]
  • Guterman SK, Howitt CL. Rifampicin supersensitivity of rho strains of E. coli, and suppression by sur mutation. Mol Gen Genet. 1979 Jan 16;169(1):27–34. [PubMed]
  • Ingram LC, Richmond MH, Sykes RB. 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. [PMC free article] [PubMed]
  • Kahn M, Kolter R, Thomas C, Figurski D, Meyer R, Remaut E, Helinski DR. Plasmid cloning vehicles derived from plasmids ColE1, F, R6K, and RK2. Methods Enzymol. 1979;68:268–280. [PubMed]
  • Malamy MH. Frameshift mutations in the lactose operon of E. coli. Cold Spring Harb Symp Quant Biol. 1966;31:189–201. [PubMed]
  • Meyer RJ, Helinski DR. Unidirectional replication of the P-group plasmid RK2. Biochim Biophys Acta. 1977 Sep 6;478(1):109–113. [PubMed]
  • Meyer R, Hinds M. Multiple mechanisms for expression of incompatibility by broad-host-range plasmid RK2. J Bacteriol. 1982 Dec;152(3):1078–1090. [PMC free article] [PubMed]
  • Meyer RJ, Shapiro JA. Genetic organization of the broad-host-range IncP-1 plasmid R751. J Bacteriol. 1980 Sep;143(3):1362–1373. [PMC free article] [PubMed]
  • Olsen RH, Shipley P. Host range and properties of the Pseudomonas aeruginosa R factor R1822. J Bacteriol. 1973 Feb;113(2):772–780. [PMC free article] [PubMed]
  • Pohlman RF, Figurski DH. Conditional lethal mutants of the kilB determinant of broad host range plasmid RK2. Plasmid. 1983 Jul;10(1):82–95. [PubMed]
  • Pohlman RF, Figurski DH. Essential genes of plasmid RK2 in Escherichia coli: trfB region controls a kil gene near trfA. J Bacteriol. 1983 Nov;156(2):584–591. [PMC free article] [PubMed]
  • Roberts JW. Termination factor for RNA synthesis. Nature. 1969 Dec 20;224(5225):1168–1174. [PubMed]
  • Roberts JW. Transcription termination and late control in phage lambda. Proc Natl Acad Sci U S A. 1975 Sep;72(9):3300–3304. [PMC free article] [PubMed]
  • Schmidhauser TJ, Filutowicz M, Helinski DR. Replication of derivatives of the broad host range plasmid RK2 in two distantly related bacteria. Plasmid. 1983 May;9(3):325–330. [PubMed]
  • Sklar J, Yot P, Weissman SM. Determination of genes, restriction sites, and DNA sequences surrounding the 6S RNA template of bacteriophage lambda. Proc Natl Acad Sci U S A. 1975 May;72(5):1817–1821. [PMC free article] [PubMed]
  • Smiley BL, Lupski JR, Svec PS, McMacken R, Godson GN. Sequences of the Escherichia coli dnaG primase gene and regulation of its expression. Proc Natl Acad Sci U S A. 1982 Aug;79(15):4550–4554. [PMC free article] [PubMed]
  • Smith CA, Thomas CM. Deletion mapping of kil and kor functions in the trfA and trfB regions of broad host range plasmid RK2. Mol Gen Genet. 1983;190(2):245–254. [PubMed]
  • Stokes HW, Moore RJ, Krishnapillai V. Complementation analysis in Pseudomonas aeruginosa of the transfer genes of the wide host range R plasmid R18. Plasmid. 1981 Mar;5(2):202–212. [PubMed]
  • Thomas CM. Molecular genetics of broad host range plasmid RK2. Plasmid. 1981 Jan;5(1):10–19. [PubMed]
  • Thomas CM. Complementation analysis of replication and maintenance functions of broad host range plasmids RK2 and RP1. Plasmid. 1981 May;5(3):277–291. [PubMed]
  • Thomas CM, Hussain AA, Smith CA. Maintenance of broad host range plasmid RK2 replicons in Pseudomonas aeruginosa. Nature. 1982 Aug 12;298(5875):674–676. [PubMed]
  • Thomas CM, Meyer R, Helinski DR. Regions of broad-host-range plasmid RK2 which are essential for replication and maintenance. J Bacteriol. 1980 Jan;141(1):213–222. [PMC free article] [PubMed]
  • Villarroel R, Hedges RW, Maenhaut R, Leemans J, Engler G, Van Montagu M, Schell J. Heteroduplex analysis of P-plasmid evolution: the role of insertion and deletion of transposable elements. Mol Gen Genet. 1983;189(3):390–399. [PubMed]
  • Wold MS, McMacken R. Regulation of expression of the Escherichia coli dnaG gene and amplification of the dnaG primase. Proc Natl Acad Sci U S A. 1982 Aug;79(16):4907–4911. [PMC free article] [PubMed]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)


Save items

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


  • MedGen
    Related information in MedGen
  • PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...