Ai. Gonzalez et al., A RACE-SPECIFIC INSERTION OF TRANSPOSABLE ELEMENT IS801 IN PSEUDOMONAS-SYRINGAE PV. PHASEOLICOLA, Molecular plant-microbe interactions, 11(5), 1998, pp. 423-428
The isolation and cloning of a random amplified polymorphic DNA-polyme
rase chain reaction (RAPD-PCR) band specific for Pseudomonas syringae
pv, phaseolicola race 1 allowed us to design a pair of primers that am
plify 1.2-kb race 1-specific and 2.7-kb race 2-specific fragments, pro
viding a rapid method for the identification of races by standard PCR
methods. Restriction analysis revealed identical endonuclease sites in
both fragments but the race 2 fragment contains a 1.5-kb insertion, i
dentified as transposable element IS801 by sequence comparison. One co
mplete and one partial open reading frame (ORF), each with a high prob
ability of encoding a protein, have been identified in the 1.2-kb frag
ment common to both race 1 and race 2 sequences. As IS801 disrupts the
partial ORF in the race 2 fragment, the complete sequence of this ORF
has been obtained as well as its promoter region. The possibility tha
t it may encode an avirulence gene is discussed as well as the role of
transposable elements in pathogen evolution.