Poster #RP121
Leifsonia xyli IS elements and their association with genome diversification.
Marcelo Marques Zerillo*, Alexandre Rossi Paschoal**, Rangel Celso Souza**, Luis Eduardo Aranha Camargo***, Claudia Barros Monteiro-Vitorello**, Marie-Anne Van Sluys*
*GaTE lab - Instituto de Biociências, São Paulo, Brazil; **LABINFO - LNCC, Petrópolis, Brazil; ***Laboratório de Genética Molecular - ESALQ, Piracicaba, Brazil
Leifsonia xyli subsp. xyli (Lxx) and Leifonia xyli subsp. cynodontis (Lxc) are closely related subspecies adapted to different plant hosts: Lxx is a sugarcane-specific pathogen and Lxc is a Cynodon grass pathogen, which can also be found associated with sugarcane causing no detectable disease symptoms. Lxx and Lxc share 91% nucleotide identity. To identify specific differences, we are sample sequencing the genome of Lxc and comparing to the complete sequenced genome of Lxx. From a total of 1.1 Mbp of non-redundant bases (approximately 50% of Lxc genome), 165,229 bp are found specific and contain 94 putative genes classified into five functional categories and other fifty-four genes related to transposable elements. BlastX results indicate that close to 50% of the specific genes have best match to proteins from non-Actinobacteria, and we speculate that they were horizontally acquired. Both bacteria share ISs (insertion sequences transposons) from families IS30, 481, 5 and 21, but the set of ISs is particular to each subspecies. Specific and/or non-syntenic fragments of Lxx and Lxc genomes are often associated with these elements. ISs are known to be potential sites for homologous recombination and DNA fragments acquisition and may also be involved in Leifsonia genome diversification.