VIEW ARTICLE

Physiology and Biochemistry

Immunological Comparison and Characterization of Ribosomes of Xanthomonas vesicatoria. N. W. Schaad, Assistant Professor, Department of Plant Pathology, University of Georgia College of Agriculture Experiment Stations, Georgia Station, Experiment 30212; Phytopathology 66:770-776. Accepted for publication 3 December 1975. DOI: 10.1094/Phyto-66-770.

Ribosomes from 25 isolates of Xanthomonas vesicatoria have been compared and characterized immunologically. Using Ouchterlony double-diffusion tests, two lines of precipitin were detected. One precipitin, designated R-1, was always present in homologous systems, was specific at the subspecies level, and was identified as a trypsin, ribonuclease-insensitive immunogen of the 50S subunit core particle. The other precipitin, designated R-2, was not always present in homologous systems, and therefore was of no comparative value. The R-2 precipitin was identified as a ribonucleic acid species of the 50S subunit. Based on the R-1 immunogen, the 25 isolates of X. vesicatoria were grouped into three serotypes. Ribosomes of X. vesicatoria failed to react with ribosomes from 15 other closely and distantly related bacteria. Therefore, it is suggested that the molecular structure of ribosomes of different species is distinct. It is further suggested that differences in ribosomal structure can be used to distinguish bacterial strains. The possible application of ribosomal immunology as a tool in identifying specific strains of pathogenic bacteria is discussed.