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Francis E. Nano - One of the best experts on this subject based on the ideXlab platform.
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Synthetic promoters functional in Francisella novicida and Escherichia coli.
Applied and environmental microbiology, 2013Co-Authors: Ralph L. Mcwhinnie, Francis E. NanoAbstract:In this work, we describe the identification of synthetic, controllable promoters that function in the bacterial pathogen Francisella novicida, a model facultative intracellular pathogen. Synthetic DNA fragments consisting of the tetracycline operator (tetO) flanked by a random nucleotide sequence were inserted into a Francisella novicida shuttle plasmid upstream of a promoterless artificial operon containing the reporter genes cat and lacZ. Fragments able to promote transcription were selected for based on their ability to drive expression of the cat gene, conferring chloramphenicol resistance. Promoters of various strengths were found, many of which were repressed in the presence of the tetracycline repressor (TetR) and promoted transcription only in the presence of the TetR inducer anhydrotetracycline. A subset of both constitutive and inducible synthetic promoters were characterized to find their induction ratios and to identify their transcription start sites. In cases where tetO was located between or downstream of the −10 and −35 regions of the promoter, control by TetR was observed. If the tetO region was upstream of the −35 region by more than 9 bp, it did not confer TetR control. We found that three of three promoters isolated in F. novicida functioned at a comparable level in E. coli; however, none of the 10 promoters isolated in E. coli functioned at a significant level in F. novicida. Our results allowed us to isolate minimal F. novicida promoters of 47 and 48 bp in length.
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Generation of protection against Francisella novicida in mice depends on the pathogenicity protein PdpA, but not PdpC or PdpD
Microbes and infection, 2013Co-Authors: Alicia Y. Chou, Francis E. Nano, Crystal L. Schmerk, Nikki J. Kennett, Eli B. Nix, Karen L. ElkinsAbstract:Abstract Previous results suggest that mutations in most genes in the Francisella pathogenicity island (FPI) attenuate the bacterium. Using a mouse model, here we determined the impact of mutations in pdpA, pdpC, and pdpD in Francisella novicida on in vitro replication in macrophages, and in vivo immunogenicity. In contrast to most FPI genes, deletion of pdpC (FnΔpdpC) and pdpD (FnΔpdpD) from F. novicida did not impact growth in mouse bone-marrow derived macrophages. Nonetheless, both FnΔpdpC and FnΔpdpD were highly attenuated when administered intradermally. Infected mice produced relatively normal anti-F. novicida serum antibodies. Further, splenocytes from infected mice controlled intramacrophage Francisella replication, indicating T cell priming, and mice immunized by infection with FnΔpdpC or FnΔpdpD survived secondary lethal parenteral challenge with either F. novicida or Francisella tularensis LVS. In contrast, deletion of pdpA (FnΔpdpA) ablated growth in macrophages in vitro. FnΔpdpA disseminated and replicated poorly in infected mice, accompanied by development of some anti-F. novicida serum antibodies. However, primed Th1 cells were not detected, and vaccinated mice did not survive even low dose challenge with either F. novicida or LVS. Taken together, these results suggest that successful priming of Th1 cells, and protection against lethal challenge, depends on expression of PdpA.
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The structure of the conserved type six secretion protein TssL (DotU) from Francisella novicida.
Journal of molecular biology, 2012Co-Authors: Craig S. Robb, Francis E. Nano, Alisdair B. BorastonAbstract:Type six secretion systems (T6SSs) are found in many Gram-negative bacteria and are important for their virulence or their ecological competitiveness. The multicomponent T6SSs are responsible for the translocation of effector molecules into target eukaryotic or prokaryotic cells. The Francisella pathogenicity island encodes a putative T6SS that Francisella novicida requires for intramacrophage growth and virulence during infection of rodents. Here, we present the X-ray crystal structure of the conserved type six secretion component TssL (DotU) from F. novicida. The structure of this protein, which is referred to as Ftn_TssL, revealed an all-α-helical fold that is a unique fusion of two 3-helix bundles. The sequence of Ftn_TssL shows low identity to presumed homologs that are found in most T6SSs. The structure of Ftn_TssL, however, has allowed us to provide bioinformatics evidence that the F. novicida TssL has a fold that is very likely representative for TssL forms from both T6SSs and from the distantly related B subclass of type four secretion systems. A map of sequence conservation on the TssL structure revealed a surface-exposed groove that may represent a functional site on the protein.
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Francisella tularensis Uses Cholesterol and Clathrin-Based Endocytic Mechanisms to Invade Hepatocytes
Scientific reports, 2011Co-Authors: Hong T. Law, Francis E. Nano, Ann En-ju Lin, Youra Kim, Brian Quach, Julian A. GuttmanAbstract:Francisella tularensis are highly infectious microbes that cause the disease tularemia. Although much of the bacterial burden is carried in non-phagocytic cells, the strategies these pathogens use to invade these cells remains elusive. To examine these mechanisms we developed two in vitro Francisella-based infection models that recapitulate the non-phagocytic cell infections seen in livers of infected mice. Using these models we found that Francisella novicida exploit clathrin and cholesterol dependent mechanisms to gain entry into hepatocytes. We also found that the clathrin accessory proteins AP-2 and Eps15 co-localized with invading Francisella novicida as well as the Francisella Live Vaccine Strain (LVS) during hepatocyte infections. Interestingly, caveolin, a protein involved in the invasion of Francisella in phagocytic cells, was not required for non-phagocytic cell infections. These results demonstrate a novel endocytic mechanism adopted by Francisella and highlight the divergence in strategies these pathogens utilize between non-phagocytic and phagocytic cell invasion.
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Objections to the transfer of Francisella novicida to the subspecies rank of Francisella tularensis
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Anders Johansson, Francis E. Nano, Jean Celli, Wayne Conlan, Karen L. Elkins, Mats Forsman, Paul Keim, Pär Larsson, Colin Manoil, Jeannine M. PetersenAbstract:Objections to the transfer of Francisella novicida to the subspecies rank of Francisella tularensis
Wolf D Splettstoesser - One of the best experts on this subject based on the ideXlab platform.
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description of Francisella hispaniensis sp nov isolated from human blood reclassification of Francisella novicida larson et al 1955 olsufiev et al 1959 as Francisella tularensis subsp novicida comb nov and emended description of the genus Francisella
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99 % with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98 % with Francisella piscicida GM2212T and 98.4 % with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6–91.7 % similarity to strains of F. tularensis subspecies, 91.2 % to F. novicida U112T and 84 % to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10 : 0 (17.2 %), C14 : 0 (11.2 %), C16 : 0 (13.1 %), C18 : 0 3-OH (14.2 %) and C18 : 1 ω9c (7.1 %). DNA–DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
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Description of Francisella hispaniensis sp. nov., isolated from human blood, reclassification of Francisella novicida (Larson et al. 1955) Olsufiev et al. 1959 as Francisella tularensis subsp. novicida comb. nov. and emended description of the genus
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99% with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98% with Francisella piscicida GM2212T and 98.4% with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6-91.7% similarity to strains of F. tularensis subspecies, 91.2% to F. novicida U112T and 84% to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10:0 (17.2%), C14:0 (11.2%), C16:0 (13.1%), C18:0 3-OH (14.2%) and C18:1omega9c (7.1%). DNA-DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
Birgit Huber - One of the best experts on this subject based on the ideXlab platform.
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description of Francisella hispaniensis sp nov isolated from human blood reclassification of Francisella novicida larson et al 1955 olsufiev et al 1959 as Francisella tularensis subsp novicida comb nov and emended description of the genus Francisella
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99 % with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98 % with Francisella piscicida GM2212T and 98.4 % with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6–91.7 % similarity to strains of F. tularensis subspecies, 91.2 % to F. novicida U112T and 84 % to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10 : 0 (17.2 %), C14 : 0 (11.2 %), C16 : 0 (13.1 %), C18 : 0 3-OH (14.2 %) and C18 : 1 ω9c (7.1 %). DNA–DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
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Description of Francisella hispaniensis sp. nov., isolated from human blood, reclassification of Francisella novicida (Larson et al. 1955) Olsufiev et al. 1959 as Francisella tularensis subsp. novicida comb. nov. and emended description of the genus
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99% with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98% with Francisella piscicida GM2212T and 98.4% with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6-91.7% similarity to strains of F. tularensis subspecies, 91.2% to F. novicida U112T and 84% to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10:0 (17.2%), C14:0 (11.2%), C16:0 (13.1%), C18:0 3-OH (14.2%) and C18:1omega9c (7.1%). DNA-DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
Judy M. Teale - One of the best experts on this subject based on the ideXlab platform.
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TLR4-dependent activation of inflammatory cytokine response in macrophages by Francisella elongation factor Tu.
Cellular immunology, 2011Co-Authors: Jyotika Sharma, Bibhuti B. Mishra, Judy M. TealeAbstract:The bacterial determinants of pulmonary Francisella induced inflammatory responses and their interaction with host components are not clearly defined. In this study, proteomic and immunoblot analyses showed presence of a cytoplasmic protein elongation factor Tu (EF-Tu) in the membrane fractions of virulent Francisella novicida, LVS and SchuS4, but not in an attenuated F. novicida mutant. EF-Tu was immunodominant in mice vaccinated and protected from virulent F. novicida. Moreover, recombinant EF-Tu induced macrophages to produce inflammatory cytokines in a TLR4 dependent manner. This study shows immune stimulatory properties of a cytoplasmic protein EF-Tu expressed on the membrane of virulent Francisella strains.
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Attenuated Response of Aged Mice to Respiratory Francisella novicida is Characterized By Reduced Cell Death and Absence of Subsequent Hypercytokinemia
PloS one, 2010Co-Authors: Chris A. Mares, Jyotika Sharma, Sandra S. Ojeda, Jocelyn A. Campos, Elizabeth G. Morris, Jacqueline J. Coalson, Judy M. TealeAbstract:Background Pneumonia and pulmonary infections are major causes of mortality among the growing elderly population. Age associated attenuations of various immune parameters, involved with both innate and adaptive responses are collectively known as immune senescence. These changes are likely to be involved with differences in host susceptibility to disease between young and aged individuals. Methodology/Principal Findings The objective of this study was to assess potential age related differences in the pulmonary host response in mice to the Gram-negative respiratory pathogen, Francisella novicida. We intranasally infected mice with F. novicida and compared various immune and pathological parameters of the pulmonary host response in both young and aged mice. Conclusions/Significance We observed that 20% of aged mice were able to survive an intranasal challenge with F. novicida while all of their younger cohorts died consistently within 4 to 6 days post infection. Further experiments revealed that all of the aged mice tested were initially able to control bacterial replication in the lungs as well as at distal sites of replication compared with young mice. In addition, the small cohort of aged survivors did not progress to a severe sepsis syndrome with hypercytokinemia, as did all of the young adult mice. Finally, a lack of widespread cell death in potential aged survivors coupled with a difference in cell types recruited to sites of infection within the lung confirmed an altered host response to Francisella in aged mice.
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Vaccination with an Attenuated Strain of Francisella novicida Prevents T-Cell Depletion and Protects Mice Infected with the Wild-Type Strain from Severe Sepsis
Infection and immunity, 2009Co-Authors: Jyotika Sharma, Bibhuti B. Mishra, Michelle J. Georges, Judy M. TealeAbstract:Francisella tularensis is the causative agent of zoonotic tularemia, a severe pneumonia in humans, and Francisella novicida causes a similarly severe tularemia in mice upon inhalation. The correlates of protective immunity, as well as the virulence mechanisms of this deadly pathogen, are not well understood. In the present study, we compared the host immune responses of lethally infected and vaccinated mice to highlight the host determinants of protection from this disease. Intranasal infection with an attenuated mutant (Mut) of F. novicida lacking a 58-kDa hypothetical protein protected C57BL/6 mice from a subsequent challenge with the fully virulent wild-type strain U112 via the same route. The protection conferred by Mut vaccination was associated with reduced bacterial burdens in systemic organs, as well as the absence of bacteremia. Also, there was reduced lung pathology and associated cell death in the lungs of vaccinated mice. Both vaccinated and nonvaccinated mice displayed an initial 2-day delay in upregulation of signature inflammatory mediators after challenge. Whereas the nonvaccinated mice developed severe sepsis characterized by hypercytokinemia and T-cell depletion, the vaccinated mice displayed moderated cytokine induction and contained increased numbers of alphabeta T cells. The recall response in vaccinated mice consisted of a characteristic Th1-type response in terms of cytokines, as well as antibody isotypes. Our results show that a regulated Th1 type of cell-mediated and humoral immunity in the absence of severe sepsis is associated with protection from respiratory tularemia, whereas a deregulated host response leading to severe sepsis contributes to mortality.
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Lethal pulmonary infection with Francisella novicida is associated with severe sepsis.
Journal of leukocyte biology, 2009Co-Authors: Jyotika Sharma, Bibhuti B. Mishra, Christopher G. Peña, Judy M. TealeAbstract:The bacterial or host determinants of lethality associated with respiratory Francisella infections are currently unknown. No exo- or endotoxins that contribute to the severity of this disease have been identified. However, a deregulated host immune response upon infection is characterized by an initial 36- to 48-h delay followed by a rapid and excessive inflammatory response prior to death at 72–120 h. Here, we extend these findings by comparing host immune responses between sublethal and lethal respiratory infections of mice with an attenuated transposon mutant (Mut) of F. novicida (F.n.) strain U112 (sublethal) versus the wild-type (WT) strain (lethal). Infection with WT bacteria, but not the Mut, was characterized by sustained bacteremia and systemic dissemination of the pathogen with temporal increases in bacterial burdens in liver and spleen. Severe pathology with large foci of infiltrates associated with extensive tissue damage was evident in WT-infected lungs, and Mut-infected mice displayed much reduced pathology with intact lung architecture. Similar to other experimental models of severe sepsis, WT- but not the Mut-infected mice exhibited a robust increase in numbers of Gr1+ and CD11b+ cells, while displaying a significant depletion of αβ T cells. Further, a dramatic up-regulation of multiple cytokines and chemokines was observed only in lethal WT infection. In addition, an earlier and larger increased expression of S100A9, a known mediator of sepsis, was observed in WT-infected mice. Taken together, these results show that a hyperinflammatory host immune response, culminating in severe sepsis, is responsible for the lethal outcome of respiratory tularemia.
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Lethal pulmonary infection with Francisella novicida causes depletion of alphabeta T cells from lungs.
Cellular immunology, 2009Co-Authors: Jyotika Sharma, Bibhuti B. Mishra, Judy M. TealeAbstract:Respiratory Francisella infections induce a delayed innate immune response followed by a severe sepsis like condition. In this study, mice infected intranasally with Francisella novicida showed a depletion of alphabeta T cells in lungs while exhibiting large accumulations of other leukocytes correlating with disease severity. The depleted T cells were predominantly CD4(+). The alphabeta T cells in infected mice showed significantly higher levels of Annexin V binding than those in mock control mice suggesting increased apoptosis of T cells. These results suggest that lack of transition from an innate to adaptive host response is associated with lethality of respiratory tularemia.
Hansjurgen Busse - One of the best experts on this subject based on the ideXlab platform.
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description of Francisella hispaniensis sp nov isolated from human blood reclassification of Francisella novicida larson et al 1955 olsufiev et al 1959 as Francisella tularensis subsp novicida comb nov and emended description of the genus Francisella
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99 % with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98 % with Francisella piscicida GM2212T and 98.4 % with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6–91.7 % similarity to strains of F. tularensis subspecies, 91.2 % to F. novicida U112T and 84 % to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10 : 0 (17.2 %), C14 : 0 (11.2 %), C16 : 0 (13.1 %), C18 : 0 3-OH (14.2 %) and C18 : 1 ω9c (7.1 %). DNA–DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
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Description of Francisella hispaniensis sp. nov., isolated from human blood, reclassification of Francisella novicida (Larson et al. 1955) Olsufiev et al. 1959 as Francisella tularensis subsp. novicida comb. nov. and emended description of the genus
International journal of systematic and evolutionary microbiology, 2009Co-Authors: Birgit Huber, Raquel Escudero, Hansjurgen Busse, Erik Seibold, Holger C Scholz, Pedro Anda, Peter Kampfer, Wolf D SplettstoesserAbstract:Strain FhSp1T, isolated from human blood in Spain in 2003, was studied for its taxonomic allocation. By 16S rRNA and recA gene sequencing, the strain was shown to belong to the genus Francisella. In the 16S rRNA gene sequence, Francisella sp. FhSp1T shared similarity of more than 99% with strains of Francisella tularensis subspecies and Francisella novicida U112T, 98% with Francisella piscicida GM2212T and 98.4% with Francisella philomiragia ATCC 25015T. In the recA gene sequence, Francisella sp. FhSp1T exhibited 91.6-91.7% similarity to strains of F. tularensis subspecies, 91.2% to F. novicida U112T and 84% to F. philomiragia ATCC 25017. The genus affiliation was supported by a quinone system typical of Francisella (Q-8 as the major component), a complex polar lipid profile similar to that of F. tularensis with the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminophospholipid (APL4) and a fatty acid profile consisting mainly of C10:0 (17.2%), C14:0 (11.2%), C16:0 (13.1%), C18:0 3-OH (14.2%) and C18:1omega9c (7.1%). DNA-DNA hybridization, which showed unambiguously that FhSp1T represents a novel species, and the results of biochemical tests allowed genotypic and phenotypic differentiation of the isolate from all hitherto-described Francisella species. A multiplex PCR developed in the course of this study discriminated FhSp1T from representatives of all other Francisella species and subspecies, clades A.I and A.II of F. tularensis subsp. tularensis and F. tularensis subsp. holarctica biovar japonica and also between these representatives of the genus. Therefore, we propose the name Francisella hispaniensis sp. nov., with the type strain FhSp1T (=FnSp1T =FSC454T =F62T =DSM 22475T =CCUG 58020T). Furthermore, we formally propose the transfer of the species Francisella novicida to the species Francisella tularensis as Francisella tularensis subsp. novicida comb. nov. (type strain ATCC 15482T =CCUG 33449T =CIP 56.12T). We also present an emended description of the genus Francisella.
