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In this study, we assessed the presence of vector-borne microorganisms in different species of fleas collected from different hosts in diverse areas of South-Western Europe by molecular methods. A total of 319 fleas belonging to eight different species was tested for the presence of eight microorganisms. Wolbachia spp. endosymbionts were detected in Ctenocephalides felis, Pulex irritans, Archaeopsylla erinacei and Ctenophthalmus baeticus boisseauorum specimens. Rickettsia felis, an emerging pathogen, was detected in C. felis, A. erinacei and Ct. b. boisseauorum. Rickettsia typhi, the agent of murine typhus was detected for the first time in A. erinacei and Mycobacterium spp. were detected for the first time in fleas (C. felis, P. irritans and A. erinacei). Lastly, five different species of Bartonella were detected in fleas' DNA in this study, including a possible new bacterium belonging to this genus. With this study, we updated the knowledge of the flea-borne bacteria present in the South-West of Europe reinforcing the idea about the necessity to expand and increase the current knowledge on flea-borne pathogens.

Truffles are edible mushrooms with similar morphological characteristics, that make it difficult to distinguish between highly prized truffles (such as the Périgord black T. melanosporum) and inexpensive truffles (such as the Asian Black T. indicum). These biological and economic features have led to several misidentifications and/or fraudulent profit in the truffle markets. In this paper, we investigate Matrix-assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) biotyping to identify 34 commercial fresh truffles from Europe and Asia. The MALDI-TOF MS clustering rapidly distinguished seven Tuber species identified by ITS phylogenetic analysis. The tasty T. melanosporum was clearly differentiated from the Chinese and less expensive truffles. These cheaper mushrooms were marketed as T. indicum but corresponded to a mix of three species. In total, the method confirmed misidentifications in 26% of commercial specimens. Several unknown blind-coded truffles were rapidly identified, with scores >= 2, using the Bruker Biotyper algorithm against MS databases. This study demonstrates that MALDI-TOF MS is a reliable, rapid and cheaper new tool compared with molecular methods for the identification of truffle species and could be used to control frauds in the truffle markets. It could also be useful for the certification of truffle-inoculated seedlings and/or diversity in forest ecosystems.

International audience; A rickettsial organism harboured by Amblyomma triguttatum ticks on Barrow Island, Western Australia, was discovered after reports of possible rickettsiosis among local workers. Subsequent isolation of this rickettsia (strain BWI-1) in cell culture and analysis of its phylogenetic, genotypic and phenotypic relationships with type strains of Rickettsia species with standing in nomenclature suggested that it was sufficiently divergent to warrant its classification as a new species. Multiple gene comparison of strain BWI-1 revealed degrees of sequence similarity with Rickettsia raoultii, its closest relative, of 99.58, 98.89, 97.03, 96.93 and 95.73% for the 16S rRNA, citrate synthase, ompA, ompB and sca4 genes, respectively. Serotyping in mice also demonstrated that strain BWI-1(T) was distinct from Rickettsia raoultii. Thus, we propose the naming of a new species, Rickettsia gravesii sp. nov., based on its novel genotypic and phenotypic characteristics. Strain BWI-1(T) was deposited in the ATCC, CSUR and ARRL collections under reference numbers VR-1664, CSUR R172 and RGBWI-1, respectively.

Bartonella senegalensis sp. nov. strain OS02(T) is the type strain of B. senegalensis sp. nov., a new species within the genus Bartonella. This strain, whose genome is described here, was isolated in Senegal from the soft tick Ornithodoros sonrai, the vector of relapsing fever. B. senegalensis is an aerobic, rod-shaped, Gram-negative bacterium. Here we describe the features of this organism, together with the complete genome sequence and its annotation. The 1,966,996 bp-long genome contains 1,710 protein-coding and 46 RNA genes, including 6 rRNA genes.

International audience; Coxiella-like bacteria have been recently proposed as human pathogens. Using molecular techniques, we detected Coxiella-like bacteria in the blood and serum samples of a patient with a scalp eschar, neck lymphadenopathy, severe urticaria, edema, fever, and arthralgia indicating that this organism can provide systemic complications.

Rickettsia raoultii is a tick-associated spotted fever group (SFG) organism, causing scalp eschar and neck lymphadenopathy after tick bite (SENLAT) in humans. We report here the genome sequence of R. raoultii strain Khabarovsk T (CSUR R3 T , ATCC VR-1596 T ), which was isolated from a Dermacentor silvarum tick collected in Russia.

Rickettsia prowazekii, the agent of epidemic typhus, is an obligate intracellular bacterium that is transmitted to human beings by the body louse. Several strains that differ considerably in virulence are recognized, but the genetic basis for these variations has remained unknown since the initial description of the avirulent vaccine strain nearly 70 yr ago. We use a recently developed murine model of epidemic typhus and transcriptomic, proteomic, and genetic techniques to identify the factors associated with virulence. We identified four phenotypes ofR. prowazekiithat differed in virulence, associated with the up-regulation of antiapoptotic genes or the interferon I pathway in the host cells. Transcriptional and proteomic analyses ofR. prowazekiisurface protein expression and protein methylation varied with virulence. By sequencing a virulent strain and using comparative genomics, we found hotspots of mutations in homopolymeric tracts of poly(A) and poly(T) in eight genes in an avirulent strain that split and inactivated these genes. These includedrecO, putative methyltransferase, and exported protein. Passage of the avirulent Madrid E strain in cells or in experimental animals was associated with a cascade of gene reactivations, beginning withrecO, that restored the virulent phenotype. An area of genomic plasticity appears to determine virulence inR. prowazekiiand represents an example of adaptive mutation for this pathogen.

Rickettsia australisstrain PhillipsTwas isolated in Queensland, Australia, in 1950. It is the tick-borne agent of Queensland tick typhus, a disease endemic in Australia. The 1.29-Mb genome sequence of this bacterium is highly similar to that ofRickettsia akaribut contains two plasmids.

The present study reports the complete and annotated genome sequence of the human pathogen Rickettsia slovaca strain 13-B, which was isolated from a Dermacentor tick in Slovakia in 1968. The 1.27-Mb genome provides further insights into the acquisition of virulence related to genome reduction in Rickettsia species.

Rickettsia conorii subsp. caspia is the agent of Astrakhan fever, a spotted fever group rickettsiosis endemic to Astrakhan, Russia. The present study reports the draft genome of Rickettsia conorii subsp. caspia strain A-167.

“ Rickettsia sibirica subsp. mongolitimonae ” is the agent of lymphangitis-associated rickettsiosis, an emerging human disease that has been diagnosed in Europe and Africa. The present study reports the draft genome of Rickettsia sibirica subsp. mongolitimonae strain HA-91.

Rickettsia japonica strain YH, isolated in 1984 in Japan, is the type strain of R. japonica , the tick-borne agent of Japanese spotted fever. Here, we report the 1.33-Mb genome of this rickettsial species.

Rickettsia honei strain RB T was isolated from a febrile patient on Flinders Island, Australia, in 1991 and has been demonstrated to be the agent of Flinders Island spotted fever, a disease transmitted to humans by ticks. The comparison of this 1.27-Mb genome with other Rickettsia genomes provides additional insight into the mechanisms of evolution in Rickettsia species.

Rickettsia sibirica sibirica is the causative agent of Siberian or North Asian tick typhus, a tick-borne rickettsiosis known to exist in Siberia and eastern China. Here we present the draft genome of Rickettsia sibirica sibirica strain BJ-90 isolated from Dermacentor sinicus ticks collected in Beijing, China.

We report the complete and annotated genome sequence of Rickettsia helvetica strain C9P9, which was first isolated in 1979 from Ixodes ricinus ticks in Switzerland and is considered a human pathogen.

Background The Rickettsia genus includes 25 validated species, 17 of which are proven human pathogens. Among these, the pathogenicity varies greatly, from the highly virulent R. prowazekii, which causes epidemic typhus and kills its arthropod host, to the mild pathogen R. africae, the agent of African tick-bite fever, which does not affect the fitness of its tick vector. Results We evaluated the clonality of R. africae in 70 patients and 155 ticks, and determined its genome sequence, which comprises a circular chromosome of 1,278,540 bp including a tra operon and an unstable 12,377-bp plasmid. To study the genetic characteristics associated with virulence, we compared this species to R. prowazekii, R. rickettsii and R. conorii. R. africae and R. prowazekii have, respectively, the less and most decayed genomes. Eighteen genes are present only in R. africae including one with a putative protease domain upregulated at 37°C. Conclusion Based on these data, we speculate that a loss of regulatory genes causes an increase of virulence of rickettsial species in ticks and mammals. We also speculate that in Rickettsia species virulence is mostly associated with gene loss. The genome sequence was deposited in GenBank under accession number [GenBank: NZ_AAUY01000001].