Submitted to: International Organization for Mycoplasmology
Publication Type: Abstract Only
Publication Acceptance Date: March 2, 2004
Publication Date: July 11, 2004
Citation: Davis, R.E., Dally, E.L., Zhao, Y., Jomantiene, R., Shao, J.Y. 2004. An adhesin and type iv secretion elements encoded by cryptic plasmid psku146 from the wall-less plant pathogen spiroplasma kunkelii. International Organization for Mycoplasmology. p. 134-135.
A 14.6 kbp cryptic plasmid, pSKU146, of the wall-less plant pathogenic mollicute, Spiroplasma kunkelii CR2-3X, was cloned and sequenced. The plasmid has a nucleotide content of 28 mol% G+C and contains potential protein coding regions (open reading frames, ORFs) encoding proteins that exhibit similarities to virulence-associated proteins involved in cell-to-cell adhesion and conjugal DNA transfer. Putative proteins encoded by the ORFs include a mature 96 kDa protein, designated SkARP1, highly similar to the ScARP1 adhesin protein involved in attachment of S. citri to insect vector gut membrane, and proteins containing domains similar to proteins of the Type IV secretion system in pathogenic bacteria, suggesting that the spiroplasma possesses a related secretion system. Plasmid pSKU146 also contains two identical oriT regions, each containing a nick sequence identical to that in the IncP conjugative plasmid family. Features of pSKU146 suggest that the plasmid functions as a mobile genetic element in conjugative transmission of spiroplasma pathogenicity-related genes.