Octopine and nopaline strains of Agrobacterium tumefaciens differ in virulence; molecular characterization of the virF locus

@article{Melchers1990OctopineAN,
  title={Octopine and nopaline strains of Agrobacterium tumefaciens differ in virulence; molecular characterization of the virF locus},
  author={Leo Sjoerd Melchers and Michael J. Maroney and Amke den Dulk-Ras and David V. Thompson and Hanneke A. J. Vuuren and Rob A. Schilperoort and Paul J. J. Hooykaas},
  journal={Plant Molecular Biology},
  year={1990},
  volume={14},
  pages={249-259}
}
Octopine and nopaline strains of Agrobacterium tumefaciens were found to differ in virulence on Nicotiana glauca. This difference is due to the absence of a functional virF locus, which is necessary for efficient tumorigenesis on N. glauca, from the nopaline Ti plasmids. Genetic studies and DNA sequence analysis of the virF locus revealed that virF embraces one open reading frame coding for a hydrophilic protein with a molecular mass of 22437 Da. Transcription of virF is directed from left to… 
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Complete sequence of the tumor-inducing plasmid pTiChry5 from the hypervirulent Agrobacterium tumefaciens strain Chry5.

Nopaline-type Ti plasmid of Agrobacterium encodes a VirF-like functional F-box protein

The data suggest that nopaline strains of Agrobacterium have evolved to encode a functional F-box protein VirF, which contains an active F- box domain and specifically interacts with SKP1-like (ASK) protein components of the plant ubiquitin/proteasome system.

CHAPTER 2 Translocation of the Agrobacterium tumefaciens VirD 2 and VirE 3 proteins into eukaryotic host cells

Findings show that besides the previously reported VirE2 and VirF proteins, VirD 2 and VirE3 are directly translocated from Agrobacterium into host cells via the VirB/VirD4 transport pore.

Symbiotic phenotypes and translocated effector proteins of the Mesorhizobium loti strain R7A VirB/D4 type IV secretion system

The heterologous translocation of rhizobial proteins by the Agrobacterium VirB/D4 T4SS is the first demonstration that rhzobial effector proteins are translocated into plant cells and confirms functional conservation between the M. loti and A. tumefaciens T4 SS strains.

The Agrobacterium VirE3 effector protein: a potential plant transcriptional activator

The data indicate that the translocated effector protein VirE3 is transported into the nucleus and there it may interact with the transcription factor pBrp to induce the expression of genes needed for tumor development.

Recognition of the Agrobacterium tumefaciens VirE2 Translocation Signal by the VirB/D4 Transport System Does Not Require VirE11

The results unambiguously show that the VirE1 chaperone is not essential for the recognition of the Vir E2 transport signal by the transport system and the subsequent translocation across the bacterial envelope into host cells.

Agrobacterium rhizogenes GALLS Protein Substitutes for Agrobacterium tumefaciens Single-Stranded DNA-Binding Protein VirE2

A novel gene from A. rhizogenes was isolated that restored pathogenicity to virE2 mutant A. tumefaciens and GALLS, an ssDNA-binding protein crucial for efficient T-DNA transfer and integration, was substituted for VirE2.

Analysis of Vir protein translocation from Agrobacterium tumefaciens using Saccharomyces cerevisiae as a model: evidence for transport of a novel effector protein VirE3.

A novel method to also detect trans-kingdom Vir protein transfer from Agrobacterium to yeast, using the Cre/lox system is described and it is shown that VirE2 and VirF protein transfer was inhibited by the presence of the Osa protein.

Characterization and host range of five tumorigenic Agrobacterium tumefaciens strains and possible application in plant transient transformation assays

Analysis of five poorly characterized wildtype Agrobacterium strains isolated from Euonymus, cane, cherry, Salix and apple suggests the potential use of these newly characterized A. tumefaciens strains in transient transformation assays with certain plant species.

Functional Subsets of the VirB Type IV Transport Complex Proteins Involved in the Capacity of Agrobacterium tumefaciens To Serve as a Recipient in virB-Mediated Conjugal Transfer of Plasmid RSF1010

Substantial subsets of type IV transport complex proteins are defined that are critical in allowing a strain to participate as a recipient in virB-mediated conjugal RSF1010 transfer.
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