A5085588413- Leptospirosis research and findings
- Veterinary medicine and infectious diseases
- Viral Infections and Vectors
- Mycobacterium research and diagnosis
- Zoonotic diseases and public health
- Vector-borne infectious diseases
- Tuberculosis Research and Epidemiology
- Yersinia bacterium, plague, ectoparasites research
- Bacteriophages and microbial interactions
- Humic Substances and Bio-Organic Studies
- Genomics and Phylogenetic Studies
- Syphilis Diagnosis and Treatment
- Viral gastroenteritis research and epidemiology
- Infectious Diseases and Mycology
- Bartonella species infections research
- Microbial Community Ecology and Physiology
- Plant and Fungal Interactions Research
- Antibiotic Resistance in Bacteria
- Bacterial Genetics and Biotechnology
- CRISPR and Genetic Engineering
- Burkholderia infections and melioidosis
- Reproductive tract infections research
- Dermatological diseases and infestations
- Vector-Borne Animal Diseases
- Amoebic Infections and Treatments
Institut Pasteur
2016-2025
Université Paris Cité
2020-2024
Centre National de la Recherche Scientifique
2022-2024
Institut Pasteur de Montevideo
2018-2022
National Agricultural Technology Institute
2022
Laboratoire National de Référence
2015-2020
Institut Pasteur de Nouvelle Calédonie
2020
Institut Pasteur d'Algérie
2020
Institute for Medical Research
2020
Chiba Institute of Science
2020
The causative agents of leptospirosis are responsible for an emerging zoonotic disease worldwide. One the major routes transmission is natural environment contaminated with urine a wide range reservoir animals. Soils and surface waters also host high diversity non-pathogenic Leptospira species which virulence status not clearly established. genus currently divided into 35 classified three phylogenetic clusters, supposedly correlate bacteria. In this study, total 90 strains isolated from...
Leptospira biflexa is a free-living saprophytic spirochete present in aquatic environments. We determined the genome sequence of L. biflexa, making it first to be sequenced. The has 3,590 protein-coding genes distributed across three circular replicons: major 3,604 chromosome, smaller 278-kb replicon that also carries essential genes, and third 74-kb replicon. Comparative analysis provides evidence an excellent model for study evolution; we conclude 2052 (61%) represent progenitor existed...
Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis individual pathogenic, intermediately pathogenic saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison all known infectious non-infectious with goal identifying genes related to pathogenesis mammalian host adaptation, remains key gap in field. Infectious comprised evolutionarily diverged from...
Pathogenic mechanisms of Leptospira interrogans, the causal agent leptospirosis, remain largely unknown. This is mainly due to lack tools for genetic manipulations pathogenic species. In this study, we characterized a mutant obtained by insertion transposon Himar1 into gene encoding putative lipoprotein, Loa22, which has predicted OmpA domain based on sequence identity. The resulting did not express Loa22 and was attenuated in virulence guinea pig hamster models whereas genetically...
Background Leptospirosis is the most common bacterial zoonoses and has been identified as an important emerging global public health problem in Southeast Asia. Rodents are reservoirs for human leptospirosis, but epidemiological data lacking. Methodology/Principal Findings We sampled rodents living different habitats from seven localities distributed across Asia (Thailand, Lao PDR Cambodia), between 2009 to 2010. Human isolates were also obtained close where sampled. The prevalence of...
ABSTRACT Leptospirosis is a worldwide-distributed zoonosis, endemic in tropical areas. Epidemiologic investigations of leptospirosis still rely on tedious serological identification tests. Recently, molecular typing systems based variable-number tandem-repeat (VNTR) analysis have been described and used to identify Leptospira interrogans strains. Although L. the most common species encountered human infections around world, other pathogenic species, such as kirschneri borgpetersenii , are...
Leptospires exist as saprophytic organisms that are aquatic or pathogens able to survive in water. Leptospirosis is transmitted humans through environmental surface waters contaminated by the urine of mammals, usually rodents, which chronically infected pathogenic strains. The ecology Leptospira spp. prompted us evaluate if these spirochaetes were form biofilms. This study investigated characteristics biofilm development both and species using microscopic examinations a polystyrene plate...
Leptospirosis is an important environmental disease and a major threat to human health causing at least 1 million clinical infections annually. There has recently been growing interest in understanding the lifestyle of Leptospira. However, Leptospira isolation from complex samples difficult time-consuming few tools are available identify isolates species level. Here, we propose polyphasic identification scheme, which might prove useful recover select those be submitted whole-genome...
Leptospira is a highly heterogeneous bacterial genus that can be divided into three evolutionary lineages and >300 serovars. The causative agents of leptospirosis are responsible an emerging zoonotic disease worldwide. To advance our understanding the biodiversity strains at global level, we evaluated performance whole-genome sequencing (WGS) as genus-wide strain classification genotyping tool. Herein propose set 545 conserved loci core genome MLST (cgMLST) scheme applicable to entire genus,...
Spirochetes have periplasmic flagella composed of a core surrounded by sheath. The pathogen Leptospira interrogans has four flaB (proposed subunit) and two flaA sheath genes. genes are organized in locus with flaA2 immediately upstream flaA1. In this study, flaA1 mutants were constructed transposon mutagenesis. Both still produced flagella. mutant did not produce FlaA1 but continued to FlaA2 retained normal morphology virulence hamster model infection had reduced motility. either the or...
Leptospirosis is considered an underdiagnosed disease. Although several PCR-based methods are currently in use, there little information on their comparability. In this study, four quantitative real-time PCR (qPCR) assays (SYBR green and TaqMan chemistries) targeting the secY, lfb1, lipL32 genes were evaluated as diagnostic assays. our hands, these can detect between 10(2) 10(3) bacteria/ml of pure culture, whole-blood, plasma, serum samples. three independent experiments, we found a...
Leptospirosis is a widespread zoonosis caused by pathogenic Leptospira interrogans that are transmitted asymptomatic infected rodents. Leptospiral lipoproteins and LPS have been shown to stimulate murine cells via TLRs 2 4. Host defense mechanisms remain obscure, although TLR4 has be involved in clearing Leptospira. In this study, we show double (TLR2 TLR4) knockout (DKO) mice rapidly died from severe hepatic renal failure following inoculation. Strikingly, the proinflammatory response...
Despite recent advances in our understanding of the genomics members genus Leptospira , little is known on how virulence has emerged this heterogeneous bacterial as well lifestyle pathogenic outside animal hosts. Here, we isolated 12 novel species from tropical soils, significantly increasing number to 35 and finding evidence highly unexplored biodiversity genus. Extended comparative phylogenomics pan-genome analyses at level by incorporating 26 genomes, revealed that, traditional...
A group of strains representing species the genus Leptospira , isolated from patients with leptospirosis in Mayotte (Indian Ocean), were previously found to be considerably divergent other known . This was inferred sequence analysis rrs (16S rRNA) and genetic loci suggests that they belong a novel species. Two each serogroup currently identified within this studied. Spirochaete, aerobic, motile, helix-shaped grew well at 30–37 °C, but not 13 °C or presence 8-azaguanine. Draft genomes also...
Leptospira strains were isolated from freshwater sampled at four sites in Algeria and characterized by whole-genome sequencing matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The cells spiral-shaped motile. Phylogenetic MALDI-TOF MS analyses showed that the can be clearly distinguished other described species genus Leptospira, therefore representing two novel pathogen subclade P1 saprophyte S1. names ainlahdjerensis sp. nov. (type strain...
Histone proteins bind DNA and organize the genomes of eukaryotes most archaea, whereas bacteria rely on different nucleoid-associated proteins. Homology searches have detected putative histone-fold domains in a few bacteria, but whether these function like archaeal/eukaryotic histones is unknown. Here we report that are major chromatin components Bdellovibrio bacteriovorus Leptospira interrogans. Patterns sequence evolution suggest important roles for additional bacterial clades. Crystal...
Pathogenic Leptospira are spirochete bacteria which cause leptospirosis, a re-emerging zoonotic disease of global importance. Here, we use recently described lineage environmental-adapted leptospires, evolutionarily the closest relatives highly virulent species, to explore key phenotypic traits and genetic determinants virulence. Through comprehensive approach integrating phylogenomic comparisons with in vitro vivo phenotyping studies, show that evolution towards pathogenicity is associated...
Different molecular typing methods including restriction fragment length polymorphism (RFLP) analysis with the major polymorphic tandem repeat (MPTR) probe and IS1652 probe, pulsed-field gel electrophoresis (PFGE), amplified (AFLP) analysis, PCR of hsp-65 gene (PRA) were applied to clinical water isolates Mycobacterium kansasii. RFLP MPTR PRA, PFGE, AFLP revealed five homogeneous clusters which appeared be subspecies. PRA gave patterns specific for each cluster, whereas PFGE patterns. was...
Leptospira interrogans sensu stricto is responsible for the most frequent and severe cases of human leptospirosis. The epidemiology clinical features leptospirosis are usually associated with serovars serogroups Leptospira. Because difficulties serological identification strains, we evaluated a novel PCR-based method typing L. serovars. Based upon genome sequence serovar Lai type strain 5660, 44 loci were analyzed by PCR their variability in size due to presence variable-number tandem...