A Highly Selectable and Highly Transferable Ti Plasmid to Study Conjugal Host Range and Ti Plasmid Dissemination in Complex Ecosystems

2004 ◽  
Vol 48 (1) ◽  
pp. 10-18 ◽  
Author(s):  
S. Teyssier-Cuvelle ◽  
P. Oger ◽  
C. Mougel ◽  
K. Groud ◽  
S.K. Farrand ◽  
...  
Keyword(s):  
Host Range ◽  
Ti Plasmid ◽  
Plasmid Dissemination

Host range of Agrobacterium tumefaciens is determined by the Ti plasmid

Nature ◽  
1980 ◽  
Vol 283 (5749) ◽  
pp. 794-796 ◽  
Author(s):  
M. F. Thomashow ◽  
C. G. Panagopoulos ◽  
M. P. Gordon ◽  
E. W. Nester
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Host Range ◽  
Ti Plasmid

scholarly journals Broad-Host-Range Expression Vectors with Tightly Regulated Promoters and Their Use To Examine the Influence of TraR and TraM Expression on Ti Plasmid Quorum Sensing

2008 ◽  
Vol 74 (16) ◽  
pp. 5053-5062 ◽  
Author(s):  
Sharik R. Khan ◽  
Jennifer Gaines ◽  
R. Martin Roop ◽  
Stephen K. Farrand
Keyword(s):  
Host Range ◽  
Gene Activation ◽  
Ti Plasmid ◽  
Expression Vectors ◽  
Multiple Cloning Site ◽  
Broad Host Range ◽  
Precise Control ◽  
Broad Host Range Plasmid ◽  
Cloned Gene ◽  
Ndei Site

ABSTRACT Experiments requiring strong repression and precise control of cloned genes can be difficult to conduct because of the relatively high basal level of expression of currently employed promoters. We report the construction of a family of vectors that contain a reengineered lacI q-lac promoter-operator complex in which cloned genes are strongly repressed in the absence of inducer. The vectors, all based on the broad-host-range plasmid pBBR1, are mobilizable and stably replicate at moderate copy number in representatives of the alpha- and gammaproteobacteria. Each vector contains a versatile multiple cloning site that includes an NdeI site allowing fusion of the cloned gene to the initiation codon of lacZα. In each tested bacterium, a uidA reporter fused to the promoter was not expressed at a detectable level in the absence of induction but was inducible by 10- to 100-fold, depending on the bacterium. The degree of induction was controllable by varying the concentration of inducer. When the vector was tested in Agrobacterium tumefaciens, a cloned copy of the traR gene, the product of which is needed at only a few copies per cell, did not confer activity under noninducing conditions. We used this attribute of very tight and variably regulatable control to assess the relative amounts of TraR required to activate the Ti plasmid conjugative transfer system. We identified levels of induction that gave wild-type transfer frequencies, as well as levels that induced correspondingly lower frequencies of transfer. We also used this system to show that the antiactivator TraM sets the level of intracellular TraR required for tra gene activation.

The Ti Plasmid from the Wide Host Range Agrobacterium vitis Strain Tm4: Map and Homology with Other Ti Plasmids

Plasmid ◽  
1993 ◽  
Vol 29 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Léon Otten ◽  
Jean-Claude Gérard ◽  
Patrice De Ruffray
Keyword(s):  
Host Range ◽  
Ti Plasmid ◽  
Agrobacterium Vitis ◽  
Wide Host Range ◽  
Ti Plasmids

Spontaneous formation of cointegrates of the oncogenic Ti-Plasmid and the wide-host-range P-plasmid RP4

Plasmid ◽  
1978 ◽  
Vol 1 (4) ◽  
pp. 456-467 ◽  
Author(s):  
M. Holsters ◽  
B. Silva ◽  
C. Genetello ◽  
G. Engler ◽  
F. van Vliet ◽  
...  
Keyword(s):  
Host Range ◽  
Ti Plasmid ◽  
Spontaneous Formation ◽  
Wide Host Range

scholarly journals Complete Genomic Sequence and Phylogenomics Analysis of Agrobacterium Strain AB2/73: A New Rhizobium Species with a Unique mega-Ti Plasmid

2021 ◽  
Author(s):  
Marjolein J.G. Hooykaas ◽  
Paul J.J. Hooykaas
Keyword(s):  
Comparative Genomics ◽  
Host Range ◽  
Genomic Sequence ◽  
Ti Plasmid ◽  
Virulence Determinants ◽  
High Quality ◽  
Agrobacterium Strain ◽  
Total Size ◽  
Full Genomic Sequence ◽  
Comparative Genomics Analysis

Abstract Background: The Agrobacterium strain AB2/73 has a unique host range for the induction of crown gall tumors, and contains an exceptionally large, over 500 kbp mega Ti plasmid. We used whole genome sequencing to fully characterize and comparatively analyze the complex genome of strain AB2/73, including its Ti plasmid and virulence factors. Results: We obtained a high-quality, full genomic sequence of AB2/73 by a combination of short-read Illumina sequencing and long-read Nanopore sequencing. The AB2/73 genome has a total size of 7,266,754 bp with 59.5% GC for which 7,012 genes (6,948 protein coding sequences) are predicted. Phylogenetic and comparative genomics analysis revealed that strain AB2/73 does not belong to the genus Agrobacterium, but to a new species in the genus Rhizobium, which is most related to Rhizobium tropici. In addition to the chromosome, the genome consists of 6 plasmids of which the largest two, of more than 1 Mbp, have chromid-like properties. The mega Ti plasmid is 605 kbp in size and contains two, one of which is incomplete, repABC replication units and thus appears to be a cointegrate consisting of about 175 kbp derived from an unknown Ti plasmid linked to 430 kbp from another large plasmid. In pTiAB2/73 we identified a complete set of virulence genes and two T-DNAs. Besides the previously described T-DNA we found a larger, second T-DNA containing a 6b-like onc gene and the acs gene for agrocinopine synthase. Also we identified two clusters of genes responsible for opine catabolism, including an acc-operon for agrocinopine degradation, and genes putatively involved in ridéopine catabolism. The plasmid also harbours tzs, iaaM and iaaH genes for the biosynthesis of the plant growth regulators cytokinin and auxin. Conclusions: The comparative genomics analysis of the high quality genome of strain AB2/73 provided insight into the unusual phylogeny and genetic composition of the limited host range Agrobacterium strain AB2/73. The description of its unique genomic composition and of all the virulence determinants in pTiAB2/73 will be an invaluable tool for further studies into the special host range properties of this bacterium.

scholarly journals A T-DNA from the Agrobacterium tumefaciens Limited-Host-Range Strain AB2/73 Contains a Single Oncogene

1998 ◽  
Vol 11 (5) ◽  
pp. 335-342 ◽  
Author(s):  
Léon Otten ◽  
Julien Schmidt
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Host Range ◽  
Dna Sequence ◽  
Ti Plasmid ◽  
Dna Homology ◽  
Agrobacterium Vitis ◽  
E Gene ◽  
Limited Host Range ◽  
Border Sequences ◽  
Border Sequence

Agrobacterium tumefaciens strain AB2/73 isolated from Lippia canescens has been described as a limited-host-range strain. Its tumor-inducing (Ti) plasmid has been found to lack DNA homology to known T-DNAs (L. Unger, S. F. Ziegler, G. A. Huffman, V. C. Knauf, R. Peet, L. W. Moore, M. P. Gordon, and E. W. Nester. J. Bacteriol. 164:723–730, 1985). We have isolated a T-DNA from AB2/73 by using a heterologous border sequence as a probe. The AB2/73 T-DNA sequence (3,504 bp) is flanked by canonical border sequences, has no detectable DNA homology with other T-DNAs, and contains only two genes: lsn ( Lippia strain nopaline synthaselike gene) and lso ( Lippia strain oncogene). The lso gene induces nondif-ferentiating tumors on a limited number of hosts when transferred by a Ti plasmid from a wide-host-range strain. Part of the predicted Lso protein is weakly homologous to other Agrobacterium oncoproteins encoded by rolB, rolBTR, orf13, gene e, gene 5, and gene 3′. A 28-kb fragment corresponding to the virA to virE region was cloned by using a heterologous vir fragment as probe. The AB2/73 vir region is homologous to most of the C58 virulence region; however, the virA gene is most related to the virA gene of the Agrobacterium vitis limited-host-range strain Ag162.

scholarly journals Complete genomic sequence and phylogenomics analysis of Agrobacterium strain AB2/73: a new Rhizobium species with a unique mega-Ti plasmid

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Marjolein J. G. Hooykaas ◽  
Paul J. J. Hooykaas
Keyword(s):  
Comparative Genomics ◽  
Host Range ◽  
Genomic Sequence ◽  
Ti Plasmid ◽  
Virulence Determinants ◽  
Rhizobium Tropici ◽  
High Quality ◽  
Agrobacterium Strain ◽  
Full Genomic Sequence ◽  
Comparative Genomics Analysis

Abstract Background The Agrobacterium strain AB2/73 has a unique host range for the induction of crown gall tumors, and contains an exceptionally large, over 500 kbp mega Ti plasmid. We used whole genome sequencing to fully characterize and comparatively analyze the complex genome of strain AB2/73, including its Ti plasmid and virulence factors. Results We obtained a high-quality, full genomic sequence of AB2/73 by a combination of short-read Illumina sequencing and long-read Nanopore sequencing. The AB2/73 genome has a total size of 7,266,754 bp with 59.5% GC for which 7012 genes (6948 protein coding sequences) are predicted. Phylogenetic and comparative genomics analysis revealed that strain AB2/73 does not belong to the genus Agrobacterium, but to a new species in the genus Rhizobium, which is most related to Rhizobium tropici. In addition to the chromosome, the genome consists of 6 plasmids of which the largest two, of more than 1 Mbp, have chromid-like properties. The mega Ti plasmid is 605 kbp in size and contains two, one of which is incomplete, repABC replication units and thus appears to be a cointegrate consisting of about 175 kbp derived from an unknown Ti plasmid linked to 430 kbp from another large plasmid. In pTiAB2/73 we identified a complete set of virulence genes and two T-DNAs. Besides the previously described T-DNA we found a larger, second T-DNA containing a 6b-like onc gene and the acs gene for agrocinopine synthase. Also we identified two clusters of genes responsible for opine catabolism, including an acc-operon for agrocinopine degradation, and genes putatively involved in ridéopine catabolism. The plasmid also harbours tzs, iaaM and iaaH genes for the biosynthesis of the plant growth regulators cytokinin and auxin. Conclusions The comparative genomics analysis of the high quality genome of strain AB2/73 provided insight into the unusual phylogeny and genetic composition of the limited host range Agrobacterium strain AB2/73. The description of its unique genomic composition and of all the virulence determinants in pTiAB2/73 will be an invaluable tool for further studies into the special host range properties of this bacterium.

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