Xenorhabdus

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 3123 Experts worldwide ranked by ideXlab platform

Sylvie Pages - One of the best experts on this subject based on the ideXlab platform.

  • New insight into diversity in the genus Xenorhabdus, including the description of ten novel species.
    International journal of systematic and evolutionary microbiology, 2020
    Co-Authors: Patrick Tailliez, Sylvie Pages, Nadege Ginibre, Noël Boemare
    Abstract:

    We investigated the diversity of a collection of 76 Xenorhabdus strains, isolated from at least 27 species of Steinernema nematodes and collected in 32 countries, using three complementary approaches: 16S rRNA gene sequencing, molecular typing and phenotypic characterization. The 16S rRNA gene sequences of the Xenorhabdus strains were highly conserved (similarity coefficient >95 %), suggesting that the common ancestor of the genus probably emerged between 250 and 500 million years ago. Based on comparisons of the 16S rRNA gene sequences, we identified 13 groups and seven unique sequences. This classification was confirmed by analysis of molecular typing profiles of the strains, leading to the classification of new isolates into the Xenorhabdus species described previously and the description of ten novel Xenorhabdus species: Xenorhabdus cabanillasii sp. nov. (type strain USTX62(T)=CIP 109066(T)=DSM 17905(T)), Xenorhabdus doucetiae sp. nov. (type strain FRM16(T)=CIP 109074(T)=DSM 17909(T)), Xenorhabdus griffiniae sp. nov. (type strain ID10(T)=CIP 109073(T)=DSM 17911(T)), Xenorhabdus hominickii sp. nov. (type strain KE01(T)=CIP 109072(T)=DSM 17903(T)), Xenorhabdus koppenhoeferi sp. nov. (type strain USNJ01(T)=CIP 109199(T)=DSM 18168(T)), Xenorhabdus kozodoii sp. nov. (type strain SaV(T)=CIP 109068(T)=DSM 17907(T)), Xenorhabdus mauleonii sp. nov. (type strain VC01(T)=CIP 109075(T)=DSM 17908(T)), Xenorhabdus miraniensis sp. nov. (type strain Q1(T)=CIP 109069(T)=DSM 17902(T)), Xenorhabdus romanii sp. nov. (type strain PR06-A(T)=CIP 109070(T)=DSM 17910(T)) and Xenorhabdus stockiae sp. nov. (type strain TH01(T)=CIP 109067(T)=DSM 17904(T)). The Xenorhabdus strains studied here had very similar phenotypic patterns, but phenotypic features nonetheless differentiated the following species: X. bovienii, X. cabanillasii, X. hominickii, X. kozodoii, X. nematophila, X. poinarii and X. szentirmaii. Based on phenotypic analysis, we identified two major groups of strains. Phenotypic group G(A) comprised strains able to grow at temperatures of 35-42 degrees C, whereas phenotypic group G(B) comprised strains that grew at temperatures below 35 degrees C, suggesting that some Xenorhabdus species may be adapted to tropical or temperate regions and/or influenced by the growth and development temperature of their nematode host.

  • ineluctable cheaters emergence in pathogens the case of Xenorhabdus
    Meeting 2017 LabEx TULIP, 2017
    Co-Authors: Jean-baptiste Ferdy, Sylvie Pages, Nathalie Perthuisot, Anne Lanoisnouri, Alain Givaudan
    Abstract:

    Ineluctable cheaters emergence in pathogens : the case of [i]Xenorhabdus[/i]. Meeting 2017 LabEx TULIP

  • Xenorhabdus bovienii cs03 the bacterial symbiont of the entomopathogenic nematode steinernema weiseri is a non virulent strain against lepidopteran insects
    Journal of Invertebrate Pathology, 2015
    Co-Authors: Sylvie Pages, Bernard Duvic, Patricia S Stock, Alain Givaudan, Gaelle Bisch, John G Mcmullen
    Abstract:

    Xenorhabdus bacteria (γ-proteobacteria: Enterobacteriaceae) have dual lifestyles. They have a mutualistic relationship with Steinernema nematodes (Nematoda: Steinernematidae) and are pathogenic to a wide range of insects. Each Steinernema nematode associates with a specific Xenorhabdus species. However, a Xenorhabdus species can have multiple nematode hosts. For example, Xenorhabdus bovienii (Xb) colonizes at least nine Steinernema species from two different phylogenetic clades. The Steinernema–Xb partnership has been found in association with different insect hosts. Biological and molecular data on the Steinernema jollieti–Xb strain SS-2004 pair have recently been described. In particular, the Xb SS-2004 bacteria are virulent alone after direct injection into insect, making this strain a model for studying Xb virulence. In this study, we searched for Xb strains attenuated in virulence. For this purpose, we underwent infection assays with five Steinernema spp.–Xb pairs with two insects, Galleria mellonella (Lepidoptera: Pyralidae) and Spodoptera littoralis (Lepidoptera: Noctuidae). The S. weiseri–Xb CS03 pair showed attenuated virulence and lower fitness in S. littoralis in comparison to the other nematode-bacteria pairs. Furthermore, when injected alone into the hemolymph of G. mellonella or S. littoralis, the Xb CS03 bacterial strain was the only non-virulent strain. By comparison with the virulent Xb SS-2004 strain, Xb CS03 showed an increased sensitivity to the insect antimicrobial peptides, suggesting an attenuated response to the insect humoral immunity. To our current knowledge, Xb CS03 is the first non-virulent Xb strain identified. We propose this strain as a new model for studying the Xenorhabdus virulence.

  • attenuated virulence and genomic reductive evolution in the entomopathogenic bacterial symbiont species Xenorhabdus poinarii
    Genome Biology and Evolution, 2014
    Co-Authors: Sylvie Pages, Jean-claude Ogier, Gaelle Bisch, Helene Chiapello, Claudine Medigue, Zoe Rouy, Corinne Teyssier
    Abstract:

    Bacteria of the genus Xenorhabdus are symbionts of soil entomopathogenic nematodes of the genus Steinernema. This symbiotic association constitutes an insecticidal complex active against a wide range of insect pests. Unlike other Xenorhabdus species, Xenorhabdus poinarii is avirulent when injected into insects in the absence of its nematode host. We sequenced the genome of the X. poinarii strain G6 and the closely related but virulent X. doucetiae strain FRM16. G6 had a smaller genome (500–700 kb smaller) than virulent Xenorhabdus strains and lacked genes encoding potential virulence factors (hemolysins, type 5 secretion systems, enzymes involved in the synthesis of secondary metabolites, and toxin–antitoxin systems). The genomes of all the X. poinarii strains analyzed here had a similar small size. We did not observe the accumulation of pseudogenes, insertion sequences or decrease in coding density usually seen as a sign of genomic erosion driven by genetic drift in host-adapted bacteria. Instead, genome reduction of X. poinarii seems to have been mediated by the excision of genomic blocks from the flexible genome, as reported for the genomes of attenuated free pathogenic bacteria and some facultative mutualistic bacteria growing exclusively within hosts. This evolutionary pathway probably reflects the adaptation of X. poinarii to specific host.

  • cabanillasin a new antifungal metabolite produced by entomopathogenic Xenorhabdus cabanillasii jm26
    The Journal of Antibiotics, 2013
    Co-Authors: Jessica Houard, Sylvie Pages, Alain Givaudan, Andre Aumelas, Thierry Noel, Valerie Fittonouhabi, Philippe Villainguillot, Maxime Gualtieri
    Abstract:

    Since the early 1980s, fungi have emerged as a major cause of human disease. Fungal infections are associated with high levels of morbidity and mortality, and are now recognized as an important public health problem. Gram-negative bacterial strains of genus Xenorhabdus are known to form symbiotic associations with soil-dwelling nematodes of the Steinernematidae family. We describe here the discovery of a new antifungal metabolite, cabanillasin, produced by Xenorhabdus cabanillasii. We purified this molecule by cation-exchange chromatography and reverse-phase chromatography. We then determined the chemical structure of cabanillasin by homo- and heteronuclear NMR and MS-MS. Cabanillasin was found to be active against yeasts and filamentous fungi involved in opportunistic infections.

Noël Boemare - One of the best experts on this subject based on the ideXlab platform.

  • New insight into diversity in the genus Xenorhabdus, including the description of ten novel species.
    International journal of systematic and evolutionary microbiology, 2020
    Co-Authors: Patrick Tailliez, Sylvie Pages, Nadege Ginibre, Noël Boemare
    Abstract:

    We investigated the diversity of a collection of 76 Xenorhabdus strains, isolated from at least 27 species of Steinernema nematodes and collected in 32 countries, using three complementary approaches: 16S rRNA gene sequencing, molecular typing and phenotypic characterization. The 16S rRNA gene sequences of the Xenorhabdus strains were highly conserved (similarity coefficient >95 %), suggesting that the common ancestor of the genus probably emerged between 250 and 500 million years ago. Based on comparisons of the 16S rRNA gene sequences, we identified 13 groups and seven unique sequences. This classification was confirmed by analysis of molecular typing profiles of the strains, leading to the classification of new isolates into the Xenorhabdus species described previously and the description of ten novel Xenorhabdus species: Xenorhabdus cabanillasii sp. nov. (type strain USTX62(T)=CIP 109066(T)=DSM 17905(T)), Xenorhabdus doucetiae sp. nov. (type strain FRM16(T)=CIP 109074(T)=DSM 17909(T)), Xenorhabdus griffiniae sp. nov. (type strain ID10(T)=CIP 109073(T)=DSM 17911(T)), Xenorhabdus hominickii sp. nov. (type strain KE01(T)=CIP 109072(T)=DSM 17903(T)), Xenorhabdus koppenhoeferi sp. nov. (type strain USNJ01(T)=CIP 109199(T)=DSM 18168(T)), Xenorhabdus kozodoii sp. nov. (type strain SaV(T)=CIP 109068(T)=DSM 17907(T)), Xenorhabdus mauleonii sp. nov. (type strain VC01(T)=CIP 109075(T)=DSM 17908(T)), Xenorhabdus miraniensis sp. nov. (type strain Q1(T)=CIP 109069(T)=DSM 17902(T)), Xenorhabdus romanii sp. nov. (type strain PR06-A(T)=CIP 109070(T)=DSM 17910(T)) and Xenorhabdus stockiae sp. nov. (type strain TH01(T)=CIP 109067(T)=DSM 17904(T)). The Xenorhabdus strains studied here had very similar phenotypic patterns, but phenotypic features nonetheless differentiated the following species: X. bovienii, X. cabanillasii, X. hominickii, X. kozodoii, X. nematophila, X. poinarii and X. szentirmaii. Based on phenotypic analysis, we identified two major groups of strains. Phenotypic group G(A) comprised strains able to grow at temperatures of 35-42 degrees C, whereas phenotypic group G(B) comprised strains that grew at temperatures below 35 degrees C, suggesting that some Xenorhabdus species may be adapted to tropical or temperate regions and/or influenced by the growth and development temperature of their nematode host.

  • phylogeny of photorhabdus and Xenorhabdus based on universally conserved protein coding sequences and implications for the taxonomy of these two genera proposal of new taxa x vietnamensis sp nov p luminescens subsp caribbeanensis subsp nov p luminesc
    International Journal of Systematic and Evolutionary Microbiology, 2010
    Co-Authors: Patrick Tailliez, Sylvie Pages, Nadege Ginibre, Christine Laroui, Armelle Paule, Noël Boemare
    Abstract:

    We used the information from a set of concatenated sequences from four genes (recA, gyrB, dnaN and gltX) to investigate the phylogeny of the genera Photorhabdus and Xenorhabdus (entomopathogenic bacteria associated with nematodes of the genera Heterorhabditis and Steinernema, respectively). The robustness of the phylogenetic tree obtained by this multigene approach was significantly better than that of the tree obtained by a single gene approach. The comparison of the topologies of single gene phylogenetic trees highlighted discrepancies which have implications for the classification of strains and new isolates; in particular, we propose the transfer of Photorhabdus luminescens subsp. thracensis to Photorhabdus temperata subsp. thracensis comb. nov. (type strain CIP 108426T =DSM 15199T). We found that, within the genus Xenorhabdus, strains or isolates that shared less than 97 % nucleotide identity (NI), calculated on the concatenated sequences of the four gene fragments (recA, gyrB, dnaN and gltX) encompassing 3395 nucleotides, did not belong to the same species. Thus, at the 97 % NI cutoff, we confirm the current 20 species of the genus Xenorhabdus and propose the description of a novel species, Xenorhabdus vietnamensis sp. nov. (type strain VN01T = CIP 109945T =DSM 22392T). Within each of the three current species of the genus Photorhabdus, P. asymbiotica, P. luminescens and P. temperata, strains or isolates which shared less than 97 % NI did not belong to the same subspecies. Comparisons of the four gene fragments plus the rplB gene fragment analysed separately led us to propose four novel subspecies: Photorhabdus luminescens subsp. caribbeanensis subsp. nov. (type strain HG29T =CIP 109949T =DSM 22391T), P. luminescens subsp. hainanensis subsp. nov. (type strain C8404T = CIP 109946T =DSM 22397T), P. temperata subsp. khanii subsp. nov. (type strain C1T =NC19T =CIP 109947T =DSM 3369T), and P. temperata subsp. tasmaniensis subsp. nov. (type strain T327T = CIP 109948T =DSM 22387T).

  • new insight into diversity in the genus Xenorhabdus including the description of ten novel species
    International Journal of Systematic and Evolutionary Microbiology, 2006
    Co-Authors: Patrick Tailliez, Sylvie Pages, Nadege Ginibre, Noël Boemare
    Abstract:

    We investigated the diversity of a collection of 76 Xenorhabdus strains, isolated from at least 27 species of Steinernema nematodes and collected in 32 countries, using three complementary approaches: 16S rRNA gene sequencing, molecular typing and phenotypic characterization. The 16S rRNA gene sequences of the Xenorhabdus strains were highly conserved (similarity coefficient >95 %), suggesting that the common ancestor of the genus probably emerged between 250 and 500 million years ago. Based on comparisons of the 16S rRNA gene sequences, we identified 13 groups and seven unique sequences. This classification was confirmed by analysis of molecular typing profiles of the strains, leading to the classification of new isolates into the Xenorhabdus species described previously and the description of ten novel Xenorhabdus species: Xenorhabdus cabanillasii sp. nov. (type strain USTX62T=CIP 109066T=DSM 17905T), Xenorhabdus doucetiae sp. nov. (type strain FRM16T=CIP 109074T=DSM 17909T), Xenorhabdus griffiniae sp. nov. (type strain ID10T=CIP 109073T=DSM 17911T), Xenorhabdus hominickii sp. nov. (type strain KE01T=CIP 109072T=DSM 17903T), Xenorhabdus koppenhoeferi sp. nov. (type strain USNJ01T=CIP 109199T=DSM 18168T), Xenorhabdus kozodoii sp. nov. (type strain SaVT=CIP 109068T=DSM 17907T), Xenorhabdus mauleonii sp. nov. (type strain VC01T=CIP 109075T=DSM 17908T), Xenorhabdus miraniensis sp. nov. (type strain Q1T=CIP 109069T=DSM 17902T), Xenorhabdus romanii sp. nov. (type strain PR06-AT=CIP 109070T=DSM 17910T) and Xenorhabdus stockiae sp. nov. (type strain TH01T=CIP 109067T=DSM 17904T). The Xenorhabdus strains studied here had very similar phenotypic patterns, but phenotypic features nonetheless differentiated the following species: X. bovienii, X. cabanillasii, X. hominickii, X. kozodoii, X. nematophila, X. poinarii and X. szentirmaii. Based on phenotypic analysis, we identified two major groups of strains. Phenotypic group GA comprised strains able to grow at temperatures of 35–42 °C, whereas phenotypic group GB comprised strains that grew at temperatures below 35 °C, suggesting that some Xenorhabdus species may be adapted to tropical or temperate regions and/or influenced by the growth and development temperature of their nematode host.

  • Interspecific competition between entomopathogenic nematodes (Steinernema) is modified by their bacterial symbionts (Xenorhabdus)
    BMC Evolutionary Biology, 2006
    Co-Authors: Mathieu Sicard, Julie Hinsinger, Noël Boemare, Sylvie Pages, Nathalie Brun, Catherine Moulia
    Abstract:

    BackgroundSymbioses between invertebrates and prokaryotes are biological systems of particular interest in order to study the evolution of mutualism. The symbioses between the entomopathogenic nematodes Steinernema and their bacterial symbiont Xenorhabdus are very tractable model systems. Previous studies demonstrated (i) a highly specialized relationship between each strain of nematodes and its naturally associated bacterial strain and (ii) that mutualism plays a role in several important life history traits of each partner such as access to insect host resources, dispersal and protection against various biotic and abiotic factors. The goal of the present study was to address the question of the impact of Xenorhabdus symbionts on the progression and outcome of interspecific competition between individuals belonging to different Steinernema species. For this, we monitored experimental interspecific competition between (i) two nematode species: S. carpocapsae and S. scapterisci and (ii) their respective symbionts: X. nematophila and X. innexi within an experimental insect-host (Galleria mellonella). Three conditions of competition between nematodes were tested: (i) infection of insects with aposymbiotic IJs (i.e. without symbiont) of both species (ii) infection of insects with aposymbiotic IJs of both species in presence of variable proportion of their two Xenorhabdus symbionts and (iii) infection of insects with symbiotic IJs (i.e. naturally associated with their symbionts) of both species.ResultsWe found that both the progression and the outcome of interspecific competition between entomopathogenic nematodes were influenced by their bacterial symbionts. Thus, the results obtained with aposymbiotic nematodes were totally opposite to those obtained with symbiotic nematodes. Moreover, the experimental introduction of different ratios of Xenorhabdus symbionts in the insect-host during competition between Steinernema modified the proportion of each species in the adults and in the global offspring.ConclusionWe showed that Xenorhabdus symbionts modified the competition between their Steinernema associates. This suggests that Xenorhabdus not only provides Steinernema with access to food sources but also furnishes new abilities to deal with biotic parameters such as competitors.

  • stages of infection during the tripartite interaction between Xenorhabdus nematophila its nematode vector and insect hosts
    Applied and Environmental Microbiology, 2004
    Co-Authors: Mathieu Sicard, Noël Boemare, Sylvie Pages, Michel Brehélin, Anne Lanois, Karine Brugirardricaud, Alain Givaudan
    Abstract:

    Bacteria of the genus Xenorhabdus are mutually associated with entomopathogenic nematodes of the genus Steinernema and are pathogenic to a broad spectrum of insects. The nematodes act as vectors, transmitting the bacteria to insect larvae, which die within a few days of infection. We characterized the early stages of bacterial infection in the insects by constructing a constitutive green fluorescent protein (GFP)-labeled Xenorhabdus nematophila strain. We injected the GFP-labeled bacteria into insects and monitored infection. We found that the bacteria had an extracellular life cycle in the hemolymph and rapidly colonized the anterior midgut region in Spodoptera littoralis larvae. Electron microscopy showed that the bacteria occupied the extracellular matrix of connective tissues within the muscle layers of the Spodoptera midgut. We confirmed the existence of such a specific infection site in the natural route of infection by infesting Spodoptera littoralis larvae with nematodes harboring GFP-labeled Xenorhabdus. When the infective juvenile (IJ) nematodes reached the insect gut, the bacterial cells were rapidly released from the intestinal vesicle into the nematode intestine. Xenorhabdus began to escape from the anus of the nematodes when IJs were wedged in the insect intestinal wall toward the insect hemolymph. Following their release into the insect hemocoel, GFP-labeled bacteria were found only in the anterior midgut region and hemolymph of Spodoptera larvae. Comparative infection assays conducted with another insect, Locusta migratoria, also showed early bacterial colonization of connective tissues. This work shows that the extracellular matrix acts as a particular colonization site for X. nematophila within insects.

Erko Stackebrandt - One of the best experts on this subject based on the ideXlab platform.

  • comparative analysis of antibacterial activities of Xenorhabdus species on related and non related bacteria in vivo
    Journal of Microbiology and Antimicrobials, 2010
    Co-Authors: Andras Fodor, Andrea M Fodor, Steven Forst, Joseph S Hogan, Michael G Klein, Katalin Lengyel, Gyula Saringer, Erko Stackebrandt, R A J Taylor, Eva Lehoczky
    Abstract:

    Insect-nematode-bacterium mutualistic associations provide attractive systems for discovery of inter kingdom signal compounds and antibiotics. A better understanding of the biological meaning of the inter-specific diversity of compounds with antimicrobial activity of theSteinernema-symbiont Xenorhabdus bacteria may provide options for simultaneous applications in pathogen control. Anti-bacterial activities of representative strains ofXenorhabdus budapestensis, Xenorhabdus szentirmaii, Xenorhabdus innexi, Xenorhabdus ehlersii, Xenorhabdus nematophila, Xenorhabdus bovienii and Xenorhabdus cabanillassiiwere tested on non-related (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus) bacteria and on each other by previously published bioassays. All active compounds were adsorbed by AmberliteR XAD1180. Chemical and thermal stability of antibacterial factors were determined. Antibiotic factors produced by different Xenorhabdus species against each other differ from those used against other competing bacterial genera. Anti-Xenorhabdusactivity of the cell-free medium and sensitivity of the cells of other Xenorhabdus strains negatively correlated in X. innexi and X. bovienii. Some activity remained unchanged during high pressure and 121°C for 10 min. The first comparative analysis of the intraspecific antibacterial activities of Xenorhabdus species demonstrated that some Xenorhabdusspecies with strong antibacterial activity could be co-cultured and they might be used simultaneously for pathogen control.   Key words: Xenorhabdus, autoclaveable antimicrobials, intra-generic, cross-tolerance

  • Xenorhabdus antibiotics a comparative analysis and potential utility for controlling mastitis caused by bacteria
    Journal of Applied Microbiology, 2008
    Co-Authors: G Furgani, Steven Forst, Michael G Klein, E Boszormenyi, A Fodor, A Mathefodor, J S Hogan, Z Katona, Erko Stackebrandt
    Abstract:

    Aims: The role of antibiotics produced by bacterial symbionts of entomopathogenic nematodes is to suppress growth of microbes in the soil environment. These antibiotics are active against Gram-positive and Gram-negative bacteria, and were tested against mastitis isolates from dairy cows. Methods and Results: Two bioassays were adapted for Xenorhabdus antibiotics; an overlay method on agar plates, and serially diluted, cell-free, Xenorhabdus cultures. The antimicrobial activities of the liquid cultures of 13 strains from five Xenorhabdus species were further evaluated. Antimicrobial activities of the type strains of X. nematophila, X. budapestensis and X. szentirmaii were tested on mastitis isolates of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae with both bioassays. A previously reported antibiotic from X. nematophila, nematophin, was synthesized in three steps from tryptamine and 4-methyl-2-oxovaleric acid sodium salt. Conclusions: The antibiotics of all three Xenorhabdus strains were powerful in either bioassay, but the sensitivity of the isolates differed from each other. While Kl. pneumoniae was the least susceptible, Staph. aureus had the highest sensitivity to each Xenorhabdus strain. Xenorhabdus szentirmaii and X. budapestensis were more potent antibiotic producers than X. nematophila, and raceme nematophin was ineffective against all mastitis isolates. Significance and Impact of the Study: These results indicate that Xenorhabdus antibiotics are effective against mastitis isolates and should be further evaluated for their potential in mastitis control or prevention.

  • a novel species of Xenorhabdus family enterobacteriaceae Xenorhabdus indica sp nov symbiotically associated with entomopathogenic nematode steinernema thermophilum ganguly and singh 2000
    Systematic and Applied Microbiology, 2006
    Co-Authors: Vishal S Somvanshi, Sudershan Ganguly, Elke Lang, Jolantha Swiderski, Anil Kumar Saxena, Erko Stackebrandt
    Abstract:

    Abstract In the search for novel Xenorhabdus strains in a recently described nematode species, Steinernema thermophilum , three strains (strain 28 T =DSM 17382 T , strain 42=DSM 17383 and strain 43=DSM 17384) were isolated from three independent isolation approaches from crushed mixture of infective juveniles. 16S rRNA gene sequence comparison of strains 28 T and DSM 17383 indicated identity and the phylogenetic position pointed towards an individual taxon within the phylogenetic dendrogram of Xenorhabdus type strains. The nearest phylogenetic relatives of strain 28 T were Xenorhabdus poinarii and Xenorhabdus szentirmaii (97.7% each). The three isolates were almost identical in reaction towards the API and BIOLOG substrate panels but differed in their reactions from those of the established type strains of the genus Xenorhabdus . These clear genomic and metabolic differences let us propose a new species, Xenorhabdus indica sp. nov. for the three clones. The type strain is strain 28 T , DSM 17382 T , CIP 108830 T .

  • description of four novel species of Xenorhabdus family enterobacteriaceae Xenorhabdus budapestensis sp nov Xenorhabdus ehlersii sp nov Xenorhabdus innexi sp nov and Xenorhabdus szentirmaii sp nov
    Systematic and Applied Microbiology, 2005
    Co-Authors: Katalina Lengyel, Andras Fodor, Elke Lang, Emilia Szallas, Peter Schumann, Erko Stackebrandt
    Abstract:

    Abstract The taxonomic affiliation was determined for four Xenorhabdus strains isolated from four Steinernema hosts from different countries. As compared to the five validly described Xenorhabdus species, i.e., X. nematophila, X. japonica, X. beddingii, X. bovienii and X. poinarii , these isolates represented novel species on the basis of 16S rRNA gene sequences and riboprint patterns, as well as by physiological and metabolic properties. They were named Xenorhabdus budapestensis sp. nov., type strain DSM 16342 T , isolated from Steinernema bicornutum ; Xenorhabdus ehlersii sp. nov., type strain DSM 16337 T , isolated from Steinernema serratum ; Xenorhabdus innexi sp. nov., type strain DSM 16336 T isolated from Steinernema scapterisci ; and Xenorhabdus szentirmaii sp. nov., type strain DSM 16338 T , isolated from Steinernema rarum .

  • Inability of the Polyphasic Approach to Systematics To Determine the Relatedness of the Genera Xenorhabdus and Photorhabdus
    International Journal of Systematic and Evolutionary Microbiology, 1995
    Co-Authors: Frederick A. Rainey, R. U. Ehlers, Erko Stackebrandt
    Abstract:

    Comparative analysis of the genes coding for 16S rRNA of the type strains of Xenorhabdus and Photorhabdus species indicates the close phylogenetic relationship of these two genera. However, distance matrix analyses do not unambiguously separate the symbionts of entomopathogenic nematodes according to their assignment into different genera. When various 16S rRNA gene sequences from a selection of members of the gamma subclass of Proteobacteria and outgroup taxa were used, the intrageneric relationships of Xenorhabdus species and the positions of Photorhabdus luminescens and related species changed significantly.

Alain Givaudan - One of the best experts on this subject based on the ideXlab platform.

  • ineluctable cheaters emergence in pathogens the case of Xenorhabdus
    Meeting 2017 LabEx TULIP, 2017
    Co-Authors: Jean-baptiste Ferdy, Sylvie Pages, Nathalie Perthuisot, Anne Lanoisnouri, Alain Givaudan
    Abstract:

    Ineluctable cheaters emergence in pathogens : the case of [i]Xenorhabdus[/i]. Meeting 2017 LabEx TULIP

  • comparative genomics between two Xenorhabdus bovienii strains highlights differential evolutionary scenarios within an entomopathogenic bacterial species
    Genome Biology and Evolution, 2016
    Co-Authors: Gaelle Bisch, Jean-claude Ogier, Patrick Tailliez, Alain Givaudan, Claudine Medigue, Zoe Rouy, Stephanie Vincent
    Abstract:

    Bacteria of the genus Xenorhabdus are symbionts of soil entomopathogenic nematodes of the genus Steinernema. This symbiotic association constitutes an insecticidal complex active against a wide range of insect pests. Within Xenorhabdus bovienii species, the X. bovienii CS03 strain (Xb CS03) is nonvirulent when directly injected into lepidopteran insects, and displays a low virulence when associated with its Steinernema symbiont. The genome of Xb CS03 was sequenced and compared with the genome of a virulent strain, X. bovienii SS-2004 (Xb SS-2004). The genome size and content widely differed between the two strains. Indeed, Xb CS03 had a large genome containing several specific loci involved in the inhibition of competitors, including a few NRPS-PKS loci (nonribosomal peptide synthetases and polyketide synthases) producing antimicrobial molecules. Consistently, Xb CS03 had a greater antimicrobial activity than Xb SS-2004. The Xb CS03 strain contained more pseudogenes than Xb SS-2004. Decay of genes involved in the host invasion and exploitation (toxins, invasins, or extracellular enzymes) was particularly important in Xb CS03. This may provide an explanation for the nonvirulence of the strain when injected into an insect host. We suggest that Xb CS03 and Xb SS-2004 followed divergent evolutionary scenarios to cope with their peculiar life cycle. The fitness strategy of Xb CS03 would involve competitor inhibition, whereas Xb SS-2004 would quickly and efficiently kill the insect host. Hence, Xenorhabdus strains would have widely divergent host exploitation strategies, which impact their genome structure.

  • Xenorhabdus bovienii cs03 the bacterial symbiont of the entomopathogenic nematode steinernema weiseri is a non virulent strain against lepidopteran insects
    Journal of Invertebrate Pathology, 2015
    Co-Authors: Sylvie Pages, Bernard Duvic, Patricia S Stock, Alain Givaudan, Gaelle Bisch, John G Mcmullen
    Abstract:

    Xenorhabdus bacteria (γ-proteobacteria: Enterobacteriaceae) have dual lifestyles. They have a mutualistic relationship with Steinernema nematodes (Nematoda: Steinernematidae) and are pathogenic to a wide range of insects. Each Steinernema nematode associates with a specific Xenorhabdus species. However, a Xenorhabdus species can have multiple nematode hosts. For example, Xenorhabdus bovienii (Xb) colonizes at least nine Steinernema species from two different phylogenetic clades. The Steinernema–Xb partnership has been found in association with different insect hosts. Biological and molecular data on the Steinernema jollieti–Xb strain SS-2004 pair have recently been described. In particular, the Xb SS-2004 bacteria are virulent alone after direct injection into insect, making this strain a model for studying Xb virulence. In this study, we searched for Xb strains attenuated in virulence. For this purpose, we underwent infection assays with five Steinernema spp.–Xb pairs with two insects, Galleria mellonella (Lepidoptera: Pyralidae) and Spodoptera littoralis (Lepidoptera: Noctuidae). The S. weiseri–Xb CS03 pair showed attenuated virulence and lower fitness in S. littoralis in comparison to the other nematode-bacteria pairs. Furthermore, when injected alone into the hemolymph of G. mellonella or S. littoralis, the Xb CS03 bacterial strain was the only non-virulent strain. By comparison with the virulent Xb SS-2004 strain, Xb CS03 showed an increased sensitivity to the insect antimicrobial peptides, suggesting an attenuated response to the insect humoral immunity. To our current knowledge, Xb CS03 is the first non-virulent Xb strain identified. We propose this strain as a new model for studying the Xenorhabdus virulence.

  • draft genome sequence and annotation of the entomopathogenic bacterium Xenorhabdus nematophila strain f1
    Genome Announcements, 2013
    Co-Authors: Jean-claude Ogier, Alain Givaudan, Zoe Rouy, Anne Lanois, Christine Laroui, Jerome Gouzy
    Abstract:

    ABSTRACT We report the 4.3-Mb genome sequence of Xenorhabdus nematophila strain F1, a Gram-negative bacterium that is a symbiont of the entomopathogenic nematode Steinernema carpocapsae and pathogenic by direct injection for a wide variety of insects.

  • cabanillasin a new antifungal metabolite produced by entomopathogenic Xenorhabdus cabanillasii jm26
    The Journal of Antibiotics, 2013
    Co-Authors: Jessica Houard, Sylvie Pages, Alain Givaudan, Andre Aumelas, Thierry Noel, Valerie Fittonouhabi, Philippe Villainguillot, Maxime Gualtieri
    Abstract:

    Since the early 1980s, fungi have emerged as a major cause of human disease. Fungal infections are associated with high levels of morbidity and mortality, and are now recognized as an important public health problem. Gram-negative bacterial strains of genus Xenorhabdus are known to form symbiotic associations with soil-dwelling nematodes of the Steinernematidae family. We describe here the discovery of a new antifungal metabolite, cabanillasin, produced by Xenorhabdus cabanillasii. We purified this molecule by cation-exchange chromatography and reverse-phase chromatography. We then determined the chemical structure of cabanillasin by homo- and heteronuclear NMR and MS-MS. Cabanillasin was found to be active against yeasts and filamentous fungi involved in opportunistic infections.

Heidi Goodrichblair - One of the best experts on this subject based on the ideXlab platform.

  • comparison of Xenorhabdus bovienii bacterial strain genomes reveals diversity in symbiotic functions
    BMC Genomics, 2015
    Co-Authors: Kristen E Murfin, Amy Whooley, Jonathan L Klassen, Heidi Goodrichblair
    Abstract:

    Background Xenorhabdus bacteria engage in a beneficial symbiosis with Steinernema nematodes, in part by providing activities that help kill and degrade insect hosts for nutrition. Xenorhabdus strains (members of a single species) can display wide variation in host-interaction phenotypes and genetic potential indicating that strains may differ in their encoded symbiosis factors, including secreted metabolites.

  • the Xenorhabdus nematophila nilabc genes confer the ability of Xenorhabdus spp to colonize steinernema carpocapsae nematodes
    Journal of Bacteriology, 2008
    Co-Authors: Charles E Cowles, Heidi Goodrichblair
    Abstract:

    Members of the Steinernema genus of nematodes are colonized mutualistically by members of the Xenorhabdus genus of bacteria. In nature, Steinernema carpocapsae nematodes are always found in association with Xenorhabdus nematophila bacteria. Thus, this interaction, like many microbe-host associations, appears to be species specific. X. nematophila requires the nilA, nilB, and nilC genes to colonize S. carpocapsae. In this work, we showed that of all the Xenorhabdus species examined, only X. nematophila has the nilA, nilB, and nilC genes. By exposing S. carpocapsae to other Xenorhabdus spp., we established that only X. nematophila is able to colonize S. carpocapsae; therefore, the S. carpocapsae-X. nematophila interaction is species specific. Further, we showed that introduction of the nilA, nilB, and nilC genes into other Xenorhabdus species enables them to colonize the same S. carpocapsae host tissue that is normally colonized by X. nematophila. Finally, sequence analysis supported the idea that the nil genes were horizontally acquired. Our findings indicate that a single genetic locus determines host specificity in this bacteria-animal mutualism and that host range expansion can occur through the acquisition of a small genetic element.

  • they ve got a ticket to ride Xenorhabdus nematophila steinernema carpocapsae symbiosis
    Current Opinion in Microbiology, 2007
    Co-Authors: Heidi Goodrichblair
    Abstract:

    The association between the bacterium Xenorhabdus nematophila and the nematode Steinernema carpocapsae is emerging as a model system to understand mutually beneficial symbioses. X. nematophila, but not other Xenorhabdus species, colonize a discrete region of a specific developmental stage of S. carpocapsae nematodes. Recent progress has led to the identification of bacterial genes necessary for colonization. Furthermore, new details have been elucidated regarding the morphology and physiology of the colonization site and the bacteria within it. A deeper understanding of the molecular mechanisms underlying the association of X. nematophila will undoubtedly yield insights into fundamental processes underlying the ubiquitous association of microbes with animals.

  • mutualism and pathogenesis in Xenorhabdus and photorhabdus two roads to the same destination
    Molecular Microbiology, 2007
    Co-Authors: Heidi Goodrichblair, David Clarke
    Abstract:

    Summary Photorhabdus and Xenorhabdus bacteria colonize the intestines of the infective soil-dwelling stage of entomophagous nematodes, Heterorhabditis and Steinernema, respectively. These nematodes infect susceptible insect larvae and release the bacteria into the insect blood. The bacteria kill the insect larvae and convert the cadaver into a food source suitable for nematode growth and development. After several rounds of reproduction the nematodes are recolonized by the bacteria before emerging from the insect cadaver into the soil to search for a new host. Photorhabdus and Xenorhabdus bacteria therefore engage in both pathogenic and mutualistic interactions with different invertebrate hosts as obligate components of their life cycle. In this review we aim to describe current knowledge of the molecular mechanisms utilized by Photorhabdus and Xenorhabdus to control their host-dependent interactions. Recent work has established that there is a trade-off between pathogenicity and mutualism in both these species of bacteria suggesting that the transition between these interactions must be under regulatory control. Despite the superficial similarity between the life cycles of these bacteria, it is now apparent that the molecular components of the regulatory networks controlling pathogenicity and mutualism in Photorhabdus and Xenorhabdus are very different.

Related terms

Xenorhabdus - 15 days free trial to Access Experts & Abstracts