SUMMARY Rhodococcus fascians is a Gram-positive bacterium that interacts with many plant species and induces multiple shoots through a combination of activation of dormant axillary meristems and de novo meristem formation. Although phenotypic analysis of the symptoms of infected plants clearly demonstrates a disturbance of the phytohormonal balance and an activation of the cell cycle, the actual mechanism of symptom development and the targets of the bacterial signals are unknown. To elucidate the molecular pathways that are responsive to R.
View Article and Find Full Text PDFThe role and metabolism of indole-3-acetic acid in gram-negative bacteria is well documented, but little is known about indole-3-acetic acid biosynthesis and regulation in gram-positive bacteria. The phytopathogen Rhodococcus fascians, a gram-positive organism, incites diverse developmental alterations, such as leafy galls, on a wide range of plants. Phenotypic analysis of a leafy gall suggests that auxin may play an important role in the development of the symptoms.
View Article and Find Full Text PDFArabidopsis thaliana (L.) Heynh. plants were challenged with Rhodococcus fascians at several developmental stages and using different inoculation procedures.
View Article and Find Full Text PDFThe glyoxylate cycle and the glycine cleavage system are part of conserved metabolic pathways involved in the chronic persistence of microorganisms in animal hosts. In the chromosome of the plant pathogen Rhodococcus fascians, the vic locus has been identified as a region containing genes essential for persistence inside induced leafy galls. Sequence analysis showed that this 18-kb locus is syntenic with chromosomal regions of Mycobacterium species that encompass the 'persistence' loci of these mammalian pathogens.
View Article and Find Full Text PDFThe phytopathogenic bacterium Rhodococcus fascians provokes shoot meristem formation and malformations on aerial plant parts, mainly at the axils. The interaction is accompanied by bacterial colonization of the plant surface and tissues. Upon infection, the two bacterial loci required for full virulence, fas and att, were expressed only at the sites of symptom development, although their expression profiles differed both spatially and temporally.
View Article and Find Full Text PDFThe gram-positive plant pathogen Rhodococcus fascians provokes leafy gall formation on a wide range of plants through secretion of signal molecules that interfere with the hormone balance of the host. Crucial virulence genes are located on a linear plasmid, and their expression is tightly controlled. A mutant with a mutation in a chromosomal locus that affected virulence was isolated.
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