Plasmid R6K Contains Two FunctionaloriTswhich can Assemble Simultaneously in Relaxosomesin vivo

Avila, P; Núñez, B; Cruz, Fernando de la

doi:10.1006/jmbi.1996.0447

Cited by 39 publications

(47 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Amino acid sequence analysis of the resulting TaxC protein showed that it contained the conserved motifs I, II and III of the relaxase family of proteins (Avila et al, 1996). In a previous study, taxC was cloned, and the protein purified.…”

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

“…When this sequence was merged with the previously published sequence around oriT␣ (co-ordinates 9.4 kb to 10.1 kb) (Shafferman et al, 1987), analysis of the merged sequence uncovered two potential open reading frames (ORFs). The first ORF was located next to the palindromic sequence containing oriT␣ (Avila et al, 1996), in the trailing region of the transferred strand (co-ordinates 9.8 kb to 10.4 kb in Fig. 1).…”

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

“…Nucleotides 1-485 of the sequence shown were taken from the 3Ј end of the complementary strand of sequence X05644 that contains R6K ␣-oriV (Shafferman et al, 1987). Nucleotides 474-813 are from sequence X95535 (Avila et al, 1996). Boxed sequences represent the G-site (Masai et al, 1990) and a ␥-consensus site (Miron et al, 1992).…”

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

“…The horizontal arrow indicates the ␣-LIR/oriT␣ sequence. A small vertical arrow points to the experimentally determined nic site (Avila et al, 1996). RBS indicates the proposed ribosome-binding sites.…”

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

“…plasmids containing the cloned LIR sequences could be mobilized by R6K at high frequencies (Avila et al, 1996). The TaxC relaxase, an essential protein for the nicking reaction, was purified and shown to cleave LIR-derived oligonucleotides containing the conjugative nic site in vitro.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Genes involved in conjugative DNA processing of plasmid R6K

Núñez

Avila

Cruz

1997

Molecular Microbiology

Self Cite

View full text Add to dashboard Cite

SummaryThe conjugative transfer region of the IncX plasmid R6K (TRA X ) was analysed by transposon mutagenesis and DNA sequencing. Tn5 tac1 insertional mutations localized TRA X to a 14.8 kb segment containing the ␣ origin of transfer (oriT␣), genes involved in conjugative DNA-processing (Dtr X ) and genes involved in pilus synthesis and assembly (Mpf X ). A second functional oriT, oriT ␤, was located at a distance of 5.3 kb from oriT␣ and was outside TRA X . Mpf X occupied a segment of 10 kb, as judged by the location of insertions conferring resistance to infection by the X pilusspecific phage X-2. At both sides of Mpf X there were insertions that were Tra ¹ but X-2 sensitive, suggesting that the mutations were in Dtr X . This region was sequenced and three genes were identified: taxA, taxB, and taxC. The overall organization was oriT␣-taxA-taxC-Mpf X -taxB. taxC coded for a oriT-relaxase that belongs to the VirD2 family. taxA coded for a protein of 181 amino acids that showed similarity to TraY of F-like plasmids and to the Arc-repressor superfamily. TaxB showed similarity to TraG-like proteins, a protein superfamily probably involved in coupling the relaxosome to the DNA-transport apparatus. TaxA and TaxC are required for oriT nicking in vivo. The nicking reaction was mistakenly assumed by Flashner et al. (1996) to represent a feature of the vegetative replication origins. However, insertions or deletions disrupting taxA and taxC affected conjugation but not replication of R6K. Conversely, protein , which is absolutely required for replication of R6K, was not required for conjugative transfer. In addition, protein DDP3, which is also assumed to have a role in replication, was found to be a positive modulator of bacterial conjugation. Taken together, these results rule out a direct and essential involvement of conjugation proteins in R6K vegetative replication, and also rule out the requirement of replication protein for conjugation.

show abstract

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

Section: Mapping the Region Of R6k Involved In Conjugative Transfermentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Genes involved in conjugative DNA processing of plasmid R6K

Núñez

Avila

Cruz

1997

Molecular Microbiology

Self Cite

View full text Add to dashboard Cite

show abstract

PlasmidDNAReplication

Tolmasky

Actis

Crosa

1999

Encyclopedia of Bioprocess Technology

View full text Add to dashboard Cite

PlasmidDNAReplication

Tolmasky

Actis

Crosa

2010

Encyclopedia of Industrial Biotechnology

View full text Add to dashboard Cite

Plasmids are extrachromosomal replicons found in gram‐negative and gram‐positive bacteria as well as in some lower eukaryotic organisms. They are present in bacterial cells replicating at a specific number of copies per cell. Their size varies from a few to several hundred kilobase pairs and bacterial cells can harbor more than one plasmid species. The medical importance of plasmids that code for antibiotic resistance and those that contribute directly to microbial pathogenicity is well‐documented, is the role played by plasmids in bacteria of importance in agriculture and industry. These extrachromosomal elements are of equal importance, however, for the study of the structure and function of DNA. Plasmids utilize a wide variety of strategies to initiate and regulate their replication. In this chapter we examine the replication of plasmids ColE1, whose replication system is part of most plasmids vectors; R6K, an iteron‐containing plasmid that possesses three replica origins; plasmids belonging to the RepABC family found in a‐proteobacteria; and of pT181, a group of plasmids found in gram‐positive bacteria. In addition,we also discuss linear plasmids.

show abstract

Plasmid R6K Contains Two FunctionaloriTswhich can Assemble Simultaneously in Relaxosomesin vivo

Cited by 39 publications

References 16 publications

Genes involved in conjugative DNA processing of plasmid R6K

Genes involved in conjugative DNA processing of plasmid R6K

PlasmidDNAReplication

PlasmidDNAReplication

Contact Info

Product

Resources

About