Genome Sequence-based Insights into the Biology of the Sugarcane Pathogen Leifsonia xyli subsp. xyli
Claudia B. Monteiro-Vitorello, Marcelo Marques Zerillo, Marie-Anne Van Sluys, and Luis Eduardo Aranha Camargo
from: Plant Pathogenic Bacteria: Genomics and Molecular Biology (Edited by: Robert W. Jackson). Caister Academic Press, U.K. (2009)
Leifsonia xyli subsp. xyli (Lxx) causes ratoon stunting disease (RSD), a major worldwide disease of sugarcane. Formerly classified as Clavibacter xyli subsp. xyli, Lxx is a fastidious member of the GC-rich Actinomycetales., a taxonomic order that comprises two other genera of plant pathogens of great agricultural impact. In this review we present some interesting features of the genome of Lxx with emphasis on pathogenicity. Most striking is the observation that Lxx has a relatively large number of pseudogenes suggestive of an ongoing process of genome decay. It has been proposed that Lxx was once a free-living bacterium that is now restricted to the xylem as a consequence or cause of the accumulation of pseudogenes. This point stems from the observation that although Lxx has only been detected inhabiting the xylem of sugar cane, it carries several genes typical of free-living organism. In this review we also discuss the relevance of lateral gene transfer in the acquisition of a few genes associated with pathogenicity and the contribution of mobile genetic elements read more ...