The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Gene Review

virB1  -  type IV secretion system apparatus lytic...

Agrobacterium fabrum str. C58

This record was discontinued.
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of virB1


High impact information on virB1

  • Fluorescence-activated cell sorter analysis and fluorescence microscopy showed that the virB promoter is induced in macrophages within 3 h after infection [3].
  • These tra genes are homologous to and colinear with genes found in the virB operon of Agrobacterium tumefaciens Ti plasmids [4].
  • The amino acid sequence of PtlC shows a high degree of homology to VirB4, a protein encoded by the virB operon, which contains 11 open reading frames that are involved in the transfer of T-DNA from Agrobacterium tumefaciens to the plant cells [5].
  • A virGN54D mutant gene of M. loti caused constitutive expression of lacZ reporter gene fusions to virB1, virD4, msi059, and msi061 [6].
  • The initiation of translation of five virB ORFs occurs at codons that overlap the termination codons of the ORF immediately upstream; thus, translational coupling may be an important mechanism for efficient translation of the large virB polycistronic mRNA [7].

Biological context of virB1


Anatomical context of virB1

  • Based on hydropathy plot analysis nine of the virB ORFs encode proteins that may interact with membranes; these data support the earlier hypothesis that virB gene products may form a membrane pore or channel to mediate exit of the T-DNA copy (T-strands) from Agrobacterium into the plant cell [7].

Associations of virB1 with chemical compounds


Analytical, diagnostic and therapeutic context of virB1

  • Flow cytometry used to measure green fluorescent protein expression from the virB promoter confirmed the data from slot blots [3].


  1. Characterization of the virB operon of an Agrobacterium tumefaciens Ti plasmid: nucleotide sequence and protein analysis. Shirasu, K., Morel, P., Kado, C.I. Mol. Microbiol. (1990) [Pubmed]
  2. Transcriptional activation of Agrobacterium tumefaciens virulence gene promoters in Escherichia coli requires the A. tumefaciens RpoA gene, encoding the alpha subunit of RNA polymerase. Lohrke, S.M., Nechaev, S., Yang, H., Severinov, K., Jin, S.J. J. Bacteriol. (1999) [Pubmed]
  3. The Brucella suis virB operon is induced intracellularly in macrophages. Boschiroli, M.L., Ouahrani-Bettache, S., Foulongne, V., Michaux-Charachon, S., Bourg, G., Allardet-Servent, A., Cazevieille, C., Liautard, J.P., Ramuz, M., O'Callaghan, D. Proc. Natl. Acad. Sci. U.S.A. (2002) [Pubmed]
  4. Common ancestry between IncN conjugal transfer genes and macromolecular export systems of plant and animal pathogens. Pohlman, R.F., Genetti, H.D., Winans, S.C. Mol. Microbiol. (1994) [Pubmed]
  5. Pertussis toxin export requires accessory genes located downstream from the pertussis toxin operon. Covacci, A., Rappuoli, R. Mol. Microbiol. (1993) [Pubmed]
  6. Symbiosis-induced cascade regulation of the Mesorhizobium loti R7A VirB/D4 type IV secretion system. Hubber, A.M., Sullivan, J.T., Ronson, C.W. Mol. Plant Microbe Interact. (2007) [Pubmed]
  7. The virB operon of Agrobacterium tumefaciens pTiC58 encodes 11 open reading frames. Kuldau, G.A., De Vos, G., Owen, J., McCaffrey, G., Zambryski, P. Mol. Gen. Genet. (1990) [Pubmed]
WikiGenes - Universities