Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: February 5, 1998
Publication Date: N/A
Technical Abstract: Spiroplasmavirus SVTS2 was isolated from Spiroplasma melliferum strain TS2 by plaque assay of culture filtrates on lawns of S.citri strain M200H; the replicative form (RF) of the virus was cloned in pUC19. Use of the cloned viral RF as a hybridization probe enabled detection of homologous sequences in all group I strains, but in no other spiroplasmas, tested. A 1.5 kbp fragment of cloned RF was sequenced and found to contain features including a 177 bp sequence that was flanked by an 11-base direct repeat. Oligonucleotide pair P4/M3, designed on the basis of the cloned fragment sequence, primed a group I spiroplasma-specific polymerase chain reaction that distinguished plant pathogenic from non-plant pathogenic Spiroplasma species based on product size. The findings are consistent with the hypothesis that group I spiroplasmas descended from a common ancestor that was exposed to SVTS2- homologous sequences. Sequence deletions and recombinations were suggestive of footprints of ancestral events in the evolution of plant pathogenic species.