@article{mbs:/content/journal/micro/10.1099/mic.0.26635-0, author = "Oguiza, José A. and Rico, Arantza and Rivas, Luis A. and Sutra, Laurent and Vivian, Alan and Murillo, Jesús", title = "Pseudomonas syringae pv. phaseolicola can be separated into two genetic lineages distinguished by the possession of the phaseolotoxin biosynthetic cluster", journal= "Microbiology", year = "2004", volume = "150", number = "2", pages = "473-482", doi = "https://doi.org/10.1099/mic.0.26635-0", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.26635-0", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", keywords = "ITS, internal transcribed spacer", keywords = "HMA, heteroduplex mobility assay", keywords = "ERIC-PCR, extragenic repetitive consensus PCR", keywords = "AP-PCR, arbitrarily primed PCR", keywords = "REP-PCR, repetitive extragenic palindromic PCR", keywords = "EEL, exchangeable effector locus", keywords = "PAI, pathogenicity island", abstract = "The bean (Phaseolus spp.) plant pathogen Pseudomonas syringae pv. phaseolicola is characterized by the ability to produce phaseolotoxin (Tox+). We recently reported that the majority of the Spanish P. syringae pv. phaseolicola population is unable to synthesize this toxin (Tox−). These Tox− isolates appear to lack the entire DNA region for the biosynthesis of phaseolotoxin (argK-tox gene cluster), as shown by PCR amplification and DNA hybridization using DNA sequences specific for separated genes of this cluster. Tox+ and Tox− isolates also showed genomic divergence that included differences in ERIC-PCR and arbitrarily primed-PCR profiles. Tox+ isolates showed distinct patterns of IS801 genomic insertions and contained a chromosomal IS801 insertion that was absent from Tox− isolates. Using a heteroduplex mobility assay, sequence differences were observed only among the intergenic transcribed spacer of the five rDNA operons of the Tox− isolates. The techniques used allowed the unequivocal differentiation of isolates of P. syringae pv. phaseolicola from the closely related soybean (Glycine max) pathogen, P. syringae pv. glycinea. Finally, a pathogenicity island that is essential for the pathogenicity of P. syringae pv. phaseolicola on beans appears to be conserved among Tox+, but not among Tox− isolates, which also lacked the characteristic large plasmid that carries this pathogenicity island. It is proposed that the results presented here justify the separation of the Tox+ and Tox− P. syringae pv. phaseolicola isolates into two distinct genetic lineages, designated Pph1 and Pph2, respectively, that show relevant genomic differences that include the pathogenicity gene complement.", }