This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Lawley, T. D. Articles by Taylor, D. E. Search for Related Content PubMed PubMed Citation Articles by Lawley, T. D. Articles by Taylor, D. E.

Functional and Mutational Analysis of Conjugative Transfer Region 1 (Tra1) from the IncHI1 Plasmid R27

Departments of Biological Sciences,¹ Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2R3²

Received 12 October 2001/ Accepted 22 January 2002

The conjugative transfer region 1 (Tra1) of the IncHI1 plasmid R27 was subjected to DNA sequence analysis, mutagenesis, genetic complementation, and an H-pilus-specific phage assay. Analysis of the nucleotide sequence indicated that the Tra1 region contains genes coding for mating pair formation (Mpf) and DNA transfer replication (Dtr) and a coupling protein. Insertional disruptions of 9 of the 14 open reading frames (ORFs) in the Tra1 region resulted in a transfer-deficient phenotype. Conjugative transfer was restored for each transfer mutant by genetic complementation. An intergenic region between traH and trhR was cloned and mobilized by R27, indicating the presence of an origin of transfer (oriT). The five ORFs immediately downstream of the oriT region are involved in H-pilus production, as determined by an H-pilus-specific phage assay. Three of these ORFs encode proteins homologous to Mpf proteins from IncF plasmids. Upstream of the oriT region are four ORFs required for plasmid transfer but not H-pilus production. TraI contains sequence motifs that are characteristic of relaxases from the IncP lineage but share no overall homology to known relaxases. TraJ contains both an Arc repressor motif and a leucine zipper motif. A putative coupling protein, TraG, shares a low level of homology to the TraG family of coupling proteins and contains motifs that are important for DNA transfer. This analysis indicates that the Mpf components of R27 share a common lineage with those of the IncF transfer system, whereas the relaxase of R27 is ancestrally related to that of the IncP transfer system.

This article has been cited by other articles:

• Gunton, J. E., Gilmour, M. W., Baptista, K. P., Lawley, T. D., Taylor, D. E. (2007). Interaction between the co-inherited TraG coupling protein and the TraJ membrane-associated protein of the H-plasmid conjugative DNA transfer system resembles chromosomal DNA translocases. Microbiology 153: 428-441 [Abstract] [Full Text]  
• Elton, T. C., Holland, S. J., Frost, L. S., Hazes, B. (2005). F-Like Type IV Secretion Systems Encode Proteins with Thioredoxin Folds That Are Putative DsbC Homologues. J. Bacteriol. 187: 8267-8277 [Abstract] [Full Text]  
• Klimke, W. A., Rypien, C. D., Klinger, B., Kennedy, R. A., Rodriguez-Maillard, J. M., Frost, L. S. (2005). The mating pair stabilization protein, TraN, of the F plasmid is an outer-membrane protein with two regions that are important for its function in conjugation. Microbiology 151: 3527-3540 [Abstract] [Full Text]  
• Gunton, J. E., Gilmour, M. W., Alonso, G., Taylor, D. E. (2005). Subcellular localization and functional domains of the coupling protein, TraG, from IncHI1 plasmid R27. Microbiology 151: 3549-3561 [Abstract] [Full Text]  
• Alonso, G., Baptista, K., Ngo, T., Taylor, D. E. (2005). Transcriptional organization of the temperature-sensitive transfer system from the IncHI1 plasmid R27. Microbiology 151: 3563-3573 [Abstract] [Full Text]  
• Forns, N., Banos, R. C., Balsalobre, C., Juarez, A., Madrid, C. (2005). Temperature-Dependent Conjugative Transfer of R27: Role of Chromosome- and Plasmid-Encoded Hha and H-NS Proteins. J. Bacteriol. 187: 3950-3959 [Abstract] [Full Text]  
• Lee, K., Yong, D., Yum, J. H., Lim, Y. S., Kim, H. S., Lee, B. K., Chong, Y. (2004). Emergence of Multidrug-Resistant Salmonella enterica Serovar Typhi in Korea. Antimicrob. Agents Chemother. 48: 4130-4135 [Abstract] [Full Text]  
• Gilmour, M. W., Taylor, D. E. (2004). A Subassembly of R27-Encoded Transfer Proteins Is Dependent on TrhC Nucleoside Triphosphate-Binding Motifs for Function but Not Formation. J. Bacteriol. 186: 1606-1613 [Abstract] [Full Text]  
• Lawley, T. D., Taylor, D. E. (2003). Characterization of the Double-Partitioning Modules of R27: Correlating Plasmid Stability with Plasmid Localization. J. Bacteriol. 185: 3060-3067 [Abstract] [Full Text]  
• Lawley, T. D., Gilmour, M. W., Gunton, J. E., Tracz, D. M., Taylor, D. E. (2003). Functional and Mutational Analysis of Conjugative Transfer Region 2 (Tra2) from the IncHI1 Plasmid R27. J. Bacteriol. 185: 581-591 [Abstract] [Full Text]