Characterization of ISXax1, a novel insertion sequence restricted to Xanthomonas axonopodis pv. phaseoli (variants fuscans and non-fuscans) and Xanthomonas axonopodis pv. vesicatoria.

ISXax1 is a novel insertion sequence belonging to the IS256 and Mutator families. Dot blot, Southern blot, and PCR analyses revealed that ISXax1 is restricted to Xanthomonas axonopodis pv. phaseoli (variants fuscans and non-fuscans) and X. axonopodis pv. vesicatoria strains. Directed AFLP also showed that a high degree of polymorphism is associated with ISXax1 insertion in these strains.