Table 1.

Genetic and phenotypic differences between F. tularensis and F. novicida.

		F. tularensisa	F. novicidab	References
Genome	Size	1,892,819 bp	1,910,031 bp	Larsson et al., 2005; Rohmer et al., 2007
	Protein coding genes	1445	1731	Larsson et al., 2005; Rohmer et al., 2007
	Pseudogenes	254	14	Rohmer et al., 2007
	FPI	2 copies	1 copy	Nano et al., 2004; Larsson et al., 2005
	Restriction modification systems	1 gene	4 functional systems/6 genes	Gallagher et al., 2008
	CRISPR/Cas	No	Yes	Sampson et al., 2013; Schunder et al., 2013
	O-antigen	15 genes	12 genes; aa identity to Ft 98% to 20%	Thomas et al., 2007; Sjödin et al., 2012
	Recombination	No	Yes	Larsson et al., 2009
	IS element proliferation	Yes	No	Larsson et al., 2009
Clinical	Tularemia	Yes	No	Francis, 1925
	Transmission	Vector-borne, animal contact, inhalation of aerosols	Salt water; brackish water	Larson et al., 1955; Dennis et al., 2001; Brett et al., 2012; Whitehouse et al., 2012
Ecology	Animal hosts	Zoonotic: small mammals, lagomorphs	No	Hopla, 1974; Jellison, 1974
	Arthropod hosts	Ticks, flies, mosquitoes	No	Jellison, 1974; Petersen et al., 2009b
Virulence (LD50 by subcutaneous or intradermal route of infection)	Mice	1 CFU	Range from 10 to >107 CFU	Bell et al., 1955; Larson et al., 1955; Olsufiev et al., 1959; Owen et al., 1964; Meshcheriakova et al., 1995; Kieffer et al., 2003
	Guinea pig	1 CFU	Range from 10 to >105 CFU	Bell et al., 1955; Olsufiev et al., 1959; Meshcheriakova et al., 1995
	Rabbit	1 CFU	>108 CFU	Olsufiev et al., 1959; Meshcheriakova et al., 1995
(LD50 by intranasal or intratracheal route of infection)	Mice	<10 CFU	Approximate LD50 of 10 CFU	Lauriano et al., 2004; Pechous et al., 2008
	Fischer 344 rats	5 × 102 CFU	Approximate LD50 of 5 × 106 CFU	Ray et al., 2010
Mechanisms of pathogenicity	Cytokine induction upon cellular uptake	No	Yes	Butchar et al., 2008; Dai et al., 2013
	Inflammasome activation	Delayed	Yes	Mariathasan et al., 2006; Weiss et al., 2007b; Fernandes-Alnemri et al., 2010; Dotson et al., 2013
	CRISPR/cas mediated TLR2 evasion	No	Yes	Dai et al., 2013; Sampson and Weiss, 2013a,b
	PI3K/Akt signaling	No; miR-155 suppressed	Yes; miR-155 induced	Cremer et al., 2009
	Pulmonary cell association	Alveolar MΦ /dendritic cells	Alveolar MΦ /neutrophils	Hall et al., 2008
	O-antigen role	Intracellular replication	Complement resistance	Thomas et al., 2007; Case et al., 2014
	Knockout of iclR or galE genes attenuates virulence in mice	No	Yes	Mortensen et al., 2010; Thomas et al., 2011

^aSpecific numbers given are in reference to F. tularensis subsp. tularensis Schu S4, except for virulence which is from (Olsufiev et al., 1959) strain Schu.

^bSpecific numbers given are in reference to F. novicida U112.