Analysis of the complete nucleotide sequence of the Agrobacterium tumefaciens virB operon

Nucleic Acids Res. 1988 May 25;16(10):4621-36. doi: 10.1093/nar/16.10.4621.


The complete nucleotide sequence of the virB locus, from the octopine Ti plasmid of Agrobacterium tumefaciens strain 15955, has been determined. In the large virB-operon (9600 nucleotides) we have identified eleven open reading frames, designated virB1 to virB11. From DNA sequence analysis it is proposed that nearly all VirB products, i.e. VirB1 to VirB9, are secreted or membrane associated proteins. Interestingly, both a membrane protein (VirB4) and a potential cytoplasmic protein (VirB11) contain the consensus amino acid sequence of ATP-binding proteins. In view of the conjugative T-DNA transfer model, the VirB proteins are suggested to act at the bacterial surface and there play an important role in directing T-DNA transfer to plant cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • DNA Restriction Enzymes
  • Molecular Sequence Data
  • Nucleotide Mapping
  • Operon*
  • Plasmids
  • Rhizobium / genetics*


  • DNA Restriction Enzymes

Associated data

  • GENBANK/X06826