whole-genome sequencing reveals distinct mutational patterns in closely related laboratory and naturally propagated francisella tularensis strains全基因组测序揭示不同的突变模式密切相关的实验室和自然传播土拉杆菌内压力.pdfVIP

Whole-Genome Sequencing Reveals Distinct Mutational Patterns in Closely Related Laboratory and Naturally Propagated Francisella tularensis Strains ¨ 1 1 2,3 1 ¨ 1 Andreas Sjodin , Kerstin Svensson , Marie Lindgren , Mats Forsman , Par Larsson * ˚ ˚ 1 Division of CBRN Security and Defence, FOI - Swedish Defence Research Agency, Umea, Sweden, 2 Department of Clinical Microbiology and Clinical Bacteriology, Umea ˚ ˚ ˚ University, Umea, Sweden, 3 Laboratory for Molecular Infection Medicine Sweden (MIMS), Umea University, Umea, Sweden Abstract The F. tularensis type A strain FSC198 from Slovakia and a second strain FSC043, which has attenuated virulence, are both considered to be derivatives of the North American F. tularensis type A strain SCHU S4. These strains have been propagated under different conditions: the FSC198 has undergone natural propagation in the environment, while the strain FSC043 has been cultivated on artificial media in laboratories. Here, we have compared the genome sequences of FSC198, FSC043, and SCHU S4 to explore the possibility that the contrasting propagation conditions may have resulted in different mutational patterns. We found four insertion/deletion events (INDELs) in the strain FSC043, as compared to the SCHU S4, while no single nucleotide polymorphisms (SNPs) or variable number of tandem repeats (VNTRs) were identified. This result contrasts with previously reported findings for the strain FSC198, where eight SNPs and three