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Poster: Biology & Disease Mgmt: Bacteriology


Genome analysis of Rathayibacter toxicus strain WAC3373 from Western Australia: sequencing, assembly and annotation
M. ARIF (1), G. Busot (1), R. Mann (2), B. Rodoni (2), S. Liu (1), J. Stack (1) (1) Department of Plant Pathology, Kansas State University, U.S.A.; (2) Department of Economic Development, Jobs, Transport and Resources, Latrobe University, Australia

Annual ryegrass toxicity (ARGT) is an often fatal disease of livestock caused by Rathayibacter toxicus, a toxin producing, nematode-vectored (Anguina funesta) gram positive bacterium. R. toxicus is believed indigenous to Australia (mainly in Western Australia and South Australia) but is also present in South Africa. Complete genome information increases our understanding of the biology of R. toxicus. A complete genome of R. toxicus isolate WAC3373 (population RT-III from Western Australia) was obtained through de novo assembly (HGAP3 assembly pipeline: Hierarchical Genome Assembly Process) using PacBio sequences. The finished assembly revealed one chromosome of 2,346,032 bp length (no plasmid) with a mean coverage of 99X. The GC content was 61.5%. Annotation projected a total of 2277 genes, including 2221 coding sequences (CDS) of which 1601 genes were assigned a putative function and 620 designated as hypothetical proteins. A total of 1331 genes were assigned to COG function categories. The total number of RNA genes were 51 including, 45 tRNA CDS and 6 rRNA CDS (LSU rRNA, SSU rRNA and 5S rRNA were 3117-, 1486- and 121-bp in length, respectively). Genome analyses will provide a better understanding of the genetic constitution of this high consequence bacterium. Unique regions of the genomes were identified to develop effective diagnostic tools for plant biosecurity applications.