ISOLATION AND CHARACTERIZATION OF XANTHOMONAS EUVESICATORIA BACTERIOPHAGES
K. Gašič, M.M. Ivanović, M. Ignjatov, A. Calić, A. Obradović
Host range, plaque morphology, thermal inactivation point, genome size and restriction fragment patterns of ten bacteriophage isolates originating from soil, pepper seed and irrigation water collected from five localities in Serbia were studied. The bacteriophage isolates were selected based on their specificity to Xanthomonas euvesicatoria, causal agent of bacterial spot of pepper. The phages had similar plaque morphology, except for two isolates producing a plaque-surrounding halo in culture of X. euvesicatoria strain KFB 189. Four phage isolates were inactivated at 70ºC and six at 71ºC. All phages had genome size of approximately 22 kb and were differentiated into four types by their EcoRI and BamHI restriction fragment patterns. Examination of two phages by transmission electron microscopy classified them as A1 morphotype members of the Myoviridae family, order Caudovirales. Although specific to X. euvesicatoria, the phages were differentiated into three groups based on their ability to lyse 59 strains of this bacterium. Adsorption rates and one-step growth curves were determined for each group representative phage isolates.