This Article 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 Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bhattacharjee, M Articles by Meyer, R J Search for Related Content PubMed PubMed Citation Articles by Bhattacharjee, M Articles by Meyer, R J

research-article

Role of the origin of transfer in termination of strand transfer during bacterial conjugation.

Department of Microbiology, University of Texas, Austin 78712.

ABSTRACT

Conjugal transfer of the broad-host-range plasmid R1162 is initiated and terminated at the nic site within the 38-bp origin of transfer (oriT). Termination involves ligation of the transferred single strand by the plasmid-encoded MobA protein. Several different assays were used to identify the oriT DNA required for termination. For plasmids containing two oriTs, with transfer initiated at one and terminated at the other, the inverted repeat within oriT is important for termination. Deletion of the outer arm reduces the termination frequency; those terminations that do occur probably depend upon nicking at this oriT prior to transfer. The locations of second-site suppressor mutations indicate that base pairing between the arms of the inverted repeat is important for termination. In vitro, the inverted repeat is not required for specific cleavage of single-stranded DNA at nic, but competition experiments indicate that oriTs with the inverted repeat are preferentially cleaved. We propose that the function of the oriT inverted repeat is to trap the plasmid-encoded MobA protein at the end of a round of strand transfer, thus ensuring that the protein is available for the ligation step.

This article has been cited by other articles:

• Perez-Mendoza, D., Lucas, M., Munoz, S., Herrera-Cervera, J. A., Olivares, J., de la Cruz, F., Sanjuan, J. (2006). The Relaxase of the Rhizobium etli Symbiotic Plasmid Shows nic Site cis-Acting Preference. J. Bacteriol. 188: 7488-7499 [Abstract] [Full Text]  
• Jandle, S., Meyer, R. (2006). Stringent and Relaxed Recognition of oriT by Related Systems for Plasmid Mobilization: Implications for Horizontal Gene Transfer. J. Bacteriol. 188: 499-506 [Abstract] [Full Text]  
• Zhang, X., Zhang, S., Meyer, R. J. (2003). Molecular handcuffing of the relaxosome at the origin of conjugative transfer of the plasmid R1162. Nucleic Acids Res 31: 4762-4768 [Abstract] [Full Text]  
• Becker, E. C., Meyer, R. J. (2003). Relaxed Specificity of the R1162 Nickase: a Model for Evolution of a System for Conjugative Mobilization of Plasmids. J. Bacteriol. 185: 3538-3546 [Abstract] [Full Text]  
• Meyer, R. (2000). Identification of the mob Genes of Plasmid pSC101 and Characterization of a Hybrid pSC101-R1162 System for Conjugal Mobilization. J. Bacteriol. 182: 4875-4881 [Abstract] [Full Text]  
• Furuya, N., Komano, T. (2000). Initiation and Termination of DNA Transfer during Conjugation of IncI1 Plasmid R64: Roles of Two Sets of Inverted Repeat Sequences within oriT in Termination of R64 Transfer. J. Bacteriol. 182: 3191-3196 [Abstract] [Full Text]  
• Henderson, D., Meyer, R. (1999). The MobA-Linked Primase Is the Only Replication Protein of R1162 Required for Conjugal Mobilization. J. Bacteriol. 181: 2973-2978 [Abstract] [Full Text]  
• Stahl, L. E., Jacobs, A., Binns, A. N. (1998). The Conjugal Intermediate of Plasmid RSF1010 Inhibits Agrobacterium tumefaciens Virulence and VirB-Dependent Export of VirE2. J. Bacteriol. 180: 3933-3939 [Abstract] [Full Text]  
• Pansegrau, W., Lanka, E. (1996). Mechanisms of Initiation and Termination Reactions in Conjugative DNA Processing. INDEPENDENCE OF TIGHT SUBSTRATE BINDING AND CATALYTIC ACTIVITY OF RELAXASE (TraI) OF IncPalpha PLASMID RP4. J. Biol. Chem. 271: 13068-13076 [Abstract] [Full Text]