The Cytokinin Complex Associated With Rhodococcus fascians: Which Compounds Are Critical for Virulence?

摘要: Virulent strains of Rhodococcus fascians cause a range disease symptoms, many which can be mimicked by application cytokinin. Both virulent and avirulent produce complex cytokinins, most derived from tRNA degradation. To test the three current hypotheses regarding involvement cytokinins as virulence determinants, we used PCR to detect specific genes, previously associated with linear plasmid, including two methyl transferase genes (mt1 mt2) fas4 (dimethyl transferase), multiple R. fascians. We inoculated Pisum sativum (pea) seeds fascians, monitored plants over time compared these mock-inoculated controls. RT-qPCR monitor expression mt1, mt2, in tissues LC-MS/MS obtain comprehensive picture cytokinin complement cotyledons, roots shoots time. The presence mt1 mt2 was those classed virulent, not avirulent. Expression peaked at 9 days post-inoculation (dpi) cotyledons 15 dpi developed strain 602. Pea both contained likely have been turnover 2-methylthio cis-zeatin-derivatives. Along isopentenyladenine-type levels compounds did correlate virulence. Only novel 1- 2-methylated isopentenyladenine were uniquely infection are, therefore, causative factors symptoms.