Comparative Genomic Characterization of Francisella tularensis Strains Belonging to Low and High Virulence Subspecies

• DOI: 10.1371/journal.ppat.1000459
• Publication Date: 2009-05-28T21:32:18Z
• Authors: Mia D. Champion; Qiandong Zeng; Eli B. Nix; Francis E. Nano; Paul Keim; Chinnappa D. Kodira; Mark Borowsky; Sarah Young; Michael Koehrsen; Reinhard Engels; Matthew Pearson; Clint Howarth; Lisa Larson; Jared White; Lucia Alvarado; Mats Forsman; Scott W. Bearden; Anders Sjöstedt; Richard Titball; Stephen L. Michell; Bruce Birren; James Galagan
• Keywords: Tularemia; Francisella; Pathogenicity island; Pseudogene; Comparative Genomics; ORFS; Subspecies; Biovar

Tularemia is a geographically widespread, severely debilitating, and occasionally lethal disease in humans. It caused by infection gram-negative bacterium, Francisella tularensis. In order to better understand its potency as an etiological agent well potential biological weapon, we have completed draft assemblies report the first complete genomic characterization of five strains belonging following different subspecies (subsp.): F. tularensis subsp. FSC033, holarctica FSC257 FSC022, novicida GA99-3548 GA99-3549 strains. Here, sequencing these comparative analysis with recently available public sequences, including rare mediasiatica FSC147 strain isolate from Central Asian Region. We evidence for occurrence large-scale rearrangement events subspecies, supporting previous proposals that further phylogenetic subdivisions Type B clade are likely. also find significant enrichment disrupted or absent ORFs proximal predicted breakpoints FSC022 strain, genetic component I restriction-modification defense system. Many pseudogenes identified closely related rarely human pathogenic modulator drug activity (mdaB) (FTT0961), which encodes known NADPH quinone reductase involved oxidative stress resistance. genes exhibiting sequence similarity effectors III (T3SS) components IV secretion systems (T4SS). One genes, msrA2 (FTT1797c), has been shown mediate bacterial pathogen survival host organisms. Our findings suggest addition duplication Pathogenicity Island, acquisition individual loci, adaptation gene loss more emerged tularensis, holarctica, occurred was distinct evolutionary differentiated common ancestor. applicable future studies focused on variations pathogenesis, broader interest pathoadaptation bacteria.