Abstract
The kinetics of pilus outgrowth were examined for Escherichia coli containing pDT1942, a TnlacZ insertion derivative of the IncHI1 plasmid R27, which was derepressed for transfer. IncHI1 plasmids are thermosensitive for transfer. The pili specified by pDT1942 were examined by transmission electron microscopy after the pilus had been labeled with the H-pilus-specific bacteriophage Hgal, which had been inactivated with RNase A. H pili were extended by extrusion from the cell surface and not by the addition of pilin subunits to the pilus tip. After pili were removed by vortexing, the outgrowth of full-length pili (2 microns long) required 20 min. H pili expressed at the transfer optimal temperature (27 degrees C) remained stable after incubation at the transfer inhibitory temperature (37 degrees C), but the formation of mating aggregates was inhibited at 37 degrees C. Within 1 min of exposure of the host cell to a heat stimulus of 50 degrees C, pili vanished. Pili were observed in straight and flexible forms with a field emission scanning electron microscope, which may indicate a dynamic role for the pilus in conjugation.
Full text
PDF








Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Achtman M., Morelli G., Schwuchow S. Cell-cell interactions in conjugating Escherichia coli: role of F pili and fate of mating aggregates. J Bacteriol. 1978 Sep;135(3):1053–1061. doi: 10.1128/jb.135.3.1053-1061.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bachmann B. J. Pedigrees of some mutant strains of Escherichia coli K-12. Bacteriol Rev. 1972 Dec;36(4):525–557. doi: 10.1128/br.36.4.525-557.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradley D. E. Conjugation system of IncC plasmid RA1, and the interaction of RA1 pili with specific RNA phage C-1. Res Microbiol. 1989 Sep;140(7):439–446. doi: 10.1016/0923-2508(89)90064-8. [DOI] [PubMed] [Google Scholar]
- Bradley D. E. Determination of pili by conjugative bacterial drug resistance plasmids of incompatibility groups B, C, H, J, K, M, V, and X. J Bacteriol. 1980 Feb;141(2):828–837. doi: 10.1128/jb.141.2.828-837.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradley D. E. Morphological and serological relationships of conjugative pili. Plasmid. 1980 Sep;4(2):155–169. doi: 10.1016/0147-619x(80)90005-0. [DOI] [PubMed] [Google Scholar]
- Bradley D. E. Specification of the conjugative pili and surface mating systems of Pseudomonas plasmids. J Gen Microbiol. 1983 Aug;129(8):2545–2556. doi: 10.1099/00221287-129-8-2545. [DOI] [PubMed] [Google Scholar]
- Bradley D. E., Taylor D. E., Cohen D. R. Specification of surface mating systems among conjugative drug resistance plasmids in Escherichia coli K-12. J Bacteriol. 1980 Sep;143(3):1466–1470. doi: 10.1128/jb.143.3.1466-1470.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradley D. E. The unique conjugation system of IncHI3 plasmid MIP233. Plasmid. 1986 Jul;16(1):63–71. doi: 10.1016/0147-619x(86)90080-6. [DOI] [PubMed] [Google Scholar]
- Coetzee J. N., Bradley D. E., Fleming J., du Toit L., Hughes V. M., Hedges R. W. Phage pilH alpha: a phage which adsorbs to IncHI and IncHII plasmid-coded pili. J Gen Microbiol. 1985 May;131(5):1115–1121. doi: 10.1099/00221287-131-5-1115. [DOI] [PubMed] [Google Scholar]
- Folkhard W., Leonard K. R., Malsey S., Marvin D. A., Dubochet J., Engel A., Achtman M., Helmuth R. X-ray diffraction and electron microscope studies on the structure of bacterial F pili. J Mol Biol. 1979 May 15;130(2):145–160. doi: 10.1016/0022-2836(79)90423-6. [DOI] [PubMed] [Google Scholar]
- Lowe M. A., Holt S. C., Eisenstein B. I. Immunoelectron microscopic analysis of elongation of type 1 fimbriae in Escherichia coli. J Bacteriol. 1987 Jan;169(1):157–163. doi: 10.1128/jb.169.1.157-163.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maher D., Sherburne R., Taylor D. E. Bacteriophages for incompatibility group H plasmids: morphological and growth characteristics. Plasmid. 1991 Sep;26(2):141–146. doi: 10.1016/0147-619x(91)90055-2. [DOI] [PubMed] [Google Scholar]
- Marvin D. A., Hohn B. Filamentous bacterial viruses. Bacteriol Rev. 1969 Jun;33(2):172–209. doi: 10.1128/br.33.2.172-209.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Novotny C. P., Fives-Taylor P. Retraction of F pili. J Bacteriol. 1974 Mar;117(3):1306–1311. doi: 10.1128/jb.117.3.1306-1311.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Novotny C., Carnahan J., Brinton C. C., Jr Mechanical removal of F pili, type I pili, and flagella from Hfr and RTF donor cells and the kinetics of their reappearance. J Bacteriol. 1969 Jun;98(3):1294–1306. doi: 10.1128/jb.98.3.1294-1306.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Saul D., Lane D., Bergquist P. L. A replication region of the IncHI plasmid, R27, is highly homologous with the RepFIA replicon of F. Mol Microbiol. 1988 Mar;2(2):219–225. doi: 10.1111/j.1365-2958.1988.tb00023.x. [DOI] [PubMed] [Google Scholar]
- Sherburne R., Armstrong G. D. Examination of enterotoxigenic Escherichia coli H10407 (colonization factor antigen I+) by scanning electron microscopy with conductive staining. J Bacteriol. 1989 Sep;171(9):5202–5205. doi: 10.1128/jb.171.9.5202-5205.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Taylor D. E., Brose E. C. Restriction endonuclease mapping of R27 (TP117), an incompatibility group HI subgroup 1 plasmid from Salmonella typhimurium. Plasmid. 1985 Jan;13(1):75–77. doi: 10.1016/0147-619x(85)90058-7. [DOI] [PubMed] [Google Scholar]
- Taylor D. E., Hedges R. W., Bergquist P. L. Molecular homology and incompatibility relationships between F and IncH1 plasmids. J Gen Microbiol. 1985 Jun;131(6):1523–1530. doi: 10.1099/00221287-131-6-1523. [DOI] [PubMed] [Google Scholar]
- Taylor D. E., Levine J. G. Studies of temperature-sensitive transfer and maintenance of H incompatibility group plasmids. J Gen Microbiol. 1980 Feb;116(2):475–484. doi: 10.1099/00221287-116-2-475. [DOI] [PubMed] [Google Scholar]
- Taylor D. E. Transfer-defective and tetracycline-sensitive mutants of the incompatibility group HI plasmid R27 generated by insertion of transposon 7. Plasmid. 1983 May;9(3):227–239. doi: 10.1016/0147-619x(83)90001-x. [DOI] [PubMed] [Google Scholar]