| alterations in cerebral protein-synthesizing systems during maturation. | | 1973 | 4802996 |
| [on the pathogenesis of experimental calciphylaxis of salivary glands]. | | 1969 | 4895236 |
| human growth hormone and hypopituitargrowth retardation. | | 1969 | 4898810 |
| the distribution of tamm horsfall mucoprotein (uromucoid) in the human nephron. | | 1969 | 4906366 |
| [studies on the direct bonding of the orthodontic resin bracket to the tooth enamel. 2. the effect of pretreatment on the enamel surface]. | | 1969 | 4906741 |
| long-term total parenteral nutrition with growth, development, and positive nitrogen balance. | | 1968 | 4968812 |
| experimental variola in monkeys. i. studies on disease enhancing property of cortisone in smallpox. a preliminary report. | | 1968 | 4979039 |
| [salmonella infections, with special reference to carrier state]. | | 1970 | 4988175 |
| [a tentative experimental analysis of upright posture]. | | 1972 | 5028037 |
| reproduction of an inbred strain of culex pipiens prevented by loss of wolbachia pipientis. | | 1983 | 6404990 |
| a rickettsia-like microorganism similar to wolbachia pipientis and its occurrence in culex mosquitoes. | | 1983 | 6863975 |
| characterization of the unlinked 16s rdna and 23s-5s rrna operon of wolbachia pipientis, a prokaryotic parasite of insect gonads. | the rrna-encoding genes (rdnas) have been cloned and characterized from wolbachia pipientis (wp), the gonadial bacteria-like parasite of the mosquito culex pipiens (cp) and the moth ephestia cautella (ec). in wp from both insect species the rdnas are organized in a way which appears to be very unusual. the rrnas are encoded by two unlinked transcription units, each present in a single copy per genome. one contains the 16s rdna only, while the other is an operon encoding both the 23s and 5s rdnas ... | 1995 | 7489921 |
| wolbachia pipientis: bacterial density and unidirectional cytoplasmic incompatibility between infected populations of aedes albopictus. | unidirectional cytoplasmic incompatibility is seen when certain wolbachia-infected insect populations are crossed. two hypotheses might explain this phenomenon: superinfections with mutually incompatible strains of wolbachia producing incompatibility when crossed to individuals infected with only a single bacterial strain or, alternatively, a bacterial dosage model, with differences in wolbachia densities responsible for the incompatibility. a quantitative pcr assay was set up as a general metho ... | 1995 | 7498425 |
| organization of wolbachia pipientis in the drosophila fertilized egg and embryo revealed by an anti-wolbachia monoclonal antibody. | cytoplasmic incompatibility (ci) in drosophila is related to the presence of wolbachia, an intracellular microorganism found in many species of insects. in order to study the intracellular localization of wolbachia in eggs and embryos, we have purified the bacteria from fly embryos and subsequently generated a monoclonal antibody (mab wol-1) specific for wolbachia. indirect immunofluorescence staining using wol-1 reveals that during mitosis, wolbachia are localized near spindle poles and centros ... | 1995 | 7547474 |
| increased male fertility in tribolium confusum beetles after infection with the intracellular parasite wolbachia. | the cytoplasmically inherited microorganism wolbachia pipientis behaves like a sexually selected trait in its host, the flour beetle tribolium confusum, enhancing male fertility at the expense of female fecundity. here we show that infected females have fewer offspring than uninfected females but infected males have a large fertility advantage over uninfected males within multiply-inseminated infected or uninfected females. the male fertility effect accelerates the spread of the wolbachia throug ... | 1995 | 7800041 |
| a prokaryotic dnaa sequence in drosophila melanogaster: wolbachia infection and cytoplasmic incompatibility among laboratory strains. | using oligonucleotide primers derived from the aligned polypeptide sequences of several prokaryotic dnaa genes, we amplified from drosophila melanogaster dna a 557 bp fragment containing a single open reading frame. the predicted peptide sequence shows a significant similarity to previously characterized protein sequences that are encoded by the dnaa genes of several prokaryotes. the dnaa sequences are also detectable by pcr in dna from drosophila simulans and nasonia vitripennis flies which are ... | 1994 | 7894745 |
| taxonomic position of the rickettsiae: current knowledge. | the term rickettsiae initially encompassed all intracellular bacteria. early rickettsial taxonomy was based on a comparison of a few phenotypic characteristics and recently, molecular studies brought new bases for rickettsial taxonomy. all rickettsial species studied so far belong to the alpha and gamma groups of the proteobacteria. ehrlichiae complex groups cowdria ruminantium, anaplasma marginale and wolbachia pipientis and the related parthenogenesis and cytoplasmic incompatibility bacteria, ... | 1994 | 8117465 |
| phylogenetic analysis of the genus rickettsia by 16s rdna sequencing. | rickettsiae are gram-negative bacteria which multiply only inside host cells and need arthropods either as reservoirs or as vectors. using the polymerase chain reaction and an automated laser fluorescent dna sequencer, we amplified and sequenced the 16s rrna (rdna) of all available bacteria of the genus rickettsia. r. tsutsugamushi remained close to the other bacteria of the genus rickettsia using this technique, contrary to previous conclusions based on the study of the sta-58 protein antigen. ... | 1995 | 8525055 |
| an improved microinjection protocol for the transfer of wolbachia pipientis between infected and uninfected strains of the flour beetle tribolium confusum. | the lethality of halocarbon and other oils to hatching larvae of the flour beetle tribolium confusum limits existing microinjection protocols, because postinjection survivorship is only 5.6% of the eggs injected. we report the development of an oil-free protocol that improves survivorship fivefold. we used this protocol to transfect the cytoplasmic endosymbiont wolbachia pipientis from infected donor eggs to uninfected host eggs and observed reproductive incompatibility in 40% of the surviving, ... | 1996 | 8764685 |
| in vitro cultivation of wolbachia pipientis in an aedes albopictus cell line. | a continuous cell line, aa23, was established from eggs of a strain of the asian tiger mosquito, aedes albopictus, naturally infected with the intracellular symbiont wolbachia pipientis. the resulting cell line was shown to be persistently infected with the bacterial endosymbiont. treatment with antibiotics cured the cells of the infection. in the course of establishing this cell line it was noticed that rflps in the pcr products of two wolbachia genes from the parental mosquitoes were fixed in ... | 1997 | 9013253 |
| phylogeny and potential transmission routes of midgut-associated endosymbionts of tsetse (diptera:glossinidae). | many tsetse species (diptera: glossinidae) harbour two morphologically different intracellular endosymbiotic microorganisms associated with gut tissue: primary (p) and secondary (s) endosymbionts. the p-endosymbionts of tsetse (wigglesworthia glossinidia) are sequestered in specialized epithelial cells, bacteriocytes, which form a structure (bacteriome) in the anterior portion of the gut. phylogenetic characterization of p-endsymbionts from the three subgenera of genus glossina has shown that th ... | 1997 | 9099582 |
| ultrastructural differentiation of the genogroups in the genus ehrlichia. | ultrastructural characteristics of 15 strains and isolates of ehrlichiae belonging to three genogroups, or clades of genetically related organisms united in the genera ehrlichia, cowdria, anaplasma, neorickettsia and a strain of wolbachia pipientis which represents a fourth genogroup in this cluster of species, were studied in continuous cell culture or in vivo: e. canis (oklahoma strain and vhe isolate), e. muris (as 145), e. chaffeensis (arkansas, 91he17 and sapulpa), human granulocytic ehrlic ... | 1998 | 9511829 |
| overcoming cytoplasmic incompatibility in drosophila. | the endocellular microbe wolbachia pipientis infects a wide variety of invertebrate species, in which its presence is closely linked to a form of reproductive failure termed cytoplasmic incompatibility (ci). ci renders infected males unable to father offspring when mated to uninfected females. because ci can dramatically affect fitness in natural populations, mechanisms that abate ci can have equally large impacts on fitness. we have discovered that repeated copulation by wolbachia-infected male ... | 1998 | 9523438 |
| phylogeny and pcr-based classification of wolbachia strains using wsp gene sequences. | wolbachia are a group of intracellular inherited bacteria that infect a wide range of arthropods. they are associated with a number of different reproductive phenotypes in their hosts, such as cytoplasmic incompatibility, parthenogenesis and feminization. while it is known that the bacterial strains responsible for these different host phenotypes form a single clade within the alpha-proteobacteria, until now it has not been possible to resolve the evolutionary relationships between different wol ... | 1998 | 9569669 |
| cloning and characterization of a gene encoding the major surface protein of the bacterial endosymbiont wolbachia pipientis. | the maternally inherited intracellular symbiont wolbachia pipientis is well known for inducing a variety of reproductive abnormalities in the diverse arthropod hosts it infects. it has been implicated in causing cytoplasmic incompatibility, parthenogenesis, and the feminization of genetic males in different hosts. the molecular mechanisms by which this fastidious intracellular bacterium causes these reproductive and developmental abnormalities have not yet been determined. in this paper, we repo ... | 1998 | 9573188 |
| evolution of wolbachia pipientis transmission dynamics in insects. | wolbachia pipientis is an intracellular bacterial parasite of arthropods that enhances its transmission by manipulating host reproduction, most commonly by inducing cytoplasmic incompatibility. the discovery of isolates with modified cytoplasmic incompatibility phenotypes and others with novel virulence properties is an indication of the potential breadth of evolutionary strategies employed by wolbachia. | 1999 | 10390640 |
| wolbachia pipientis: microbial manipulator of arthropod reproduction. | the alpha-proteobacterium wolbachia pipientis is a very common cytoplasmic symbiont of insects, crustaceans, mites, and filarial nematodes. to enhance its transmission, w. pipientis has evolved a large scale of host manipulations: parthenogenesis induction, feminization, and male killing. w. pipientis's most common effect is a crossing incompatibility between infected males and uninfected females. little is known about the genetics and biochemistry of these symbionts because of their fastidious ... | 1999 | 10547686 |
| phylogenetic analysis of the 16s rdna of the cytoplasmic bacterium wolbachia from the novel host folsomia candida (hexapoda, collembola) and its implications for wolbachial taxonomy. | wolbachia pipientis are intracellular, transovarially inherited alpha-proteobacteria in invertebrates. four major wolbachia groups exist: a, b (contained in divergent arthropods), c and d (harbored by nematoda). by means of transmission electron microscopy, we observed wolbachia-like bacteria in a primitive insect, folsomia candida (hexapoda, collembola, isotomidae). 16s rdna analysis proved them to constitute a novel lineage, henceforth named group e, in the wolbachial phylogenetic tree. it sha ... | 1999 | 10556723 |
| tissue distribution and prevalence of wolbachia infections in tsetse flies, glossina spp. | tsetse flies glossina spp. (diptera: glossinidae) harbor three different symbiotic microorganisms, one being an intracellular rickettsia of the genus wolbachia. this bacterium infects a wide range of arthropods, where it causes a variety of reproductive abnormalities, one of which is termed cytoplasmic incompatibility (ci) that, when expressed, results in embryonic death due to disruptions in fertilization events. we report here that in colonized flies, wolbachia infections can be detected in 10 ... | 2000 | 10759311 |
| offsetting effects of wolbachia infection and heat shock on sperm production in drosophila simulans: analyses of fecundity, fertility and accessory gland proteins. | infection in drosophila simulans with the endocellular symbiont wolbachia pipientis results in egg lethality caused by failure to properly initiate diploid development (cytoplasmic incompatibility, ci). the relationship between wolbachia infection and reproductive factors influencing male fitness has not been well examined. here we compare infected and uninfected strains of d. simulans for (1) sperm production, (2) male fertility, and (3) the transfer and processing of two accessory gland protei ... | 2000 | 10790392 |
| comparative genomics of mitochondrial dna in drosophila simulans. | the current study compares the nucleotide variation among 22 complete mitochondrial genomes of the three distinct drosophila simulans haplotypes with intron 1 of the alcohol dehydrogenase-related locus. this is the first study to investigate the sequence variation of multiple complete mitochondrial genomes within distinct mitochondrial haplotypes of a single species. patterns of variation suggest distinct forces are influencing the evolution of mitochondrial dna (mtdna) and autosomal dna in d. s ... | 2000 | 10903373 |
| expression of cytoplasmic incompatibility in drosophila simulans and its impact on infection frequencies and distribution of wolbachia pipientis. | the aim of this study is to examine the expression of cytoplasmic incompatibility and investigate the distribution and population frequencies of wolbachia pipientis strains in drosophila simulans. nucleotide sequence data from 16s rdna and a wolbachia surface protein coding sequence and cytoplasmic incompatibility assays identify four distinct wolbachia strains: wha, wri, wma, and wau. the levels of cytoplasmic incompatibility between six lines carrying these strains of bacteria and three contro ... | 2000 | 11108593 |
| occurrence of novel verrucomicrobial species, endosymbiotic and associated with parthenogenesis in xiphinema americanum-group species (nematoda, longidoridae). | numerous micro-organisms have been described as cytoplasmic symbionts of eukaryotes. many so-called obligate endosymbionts rely exclusively on maternal (vertical or transovarial) transmission to maintain themselves, rendering them dependent on the host sex ratio, which they would tend to manipulate to their own advantage. the latter phenomenon is often associated with the presence of wolbachia pipientis (alpha-proteobacteria) in arthropods and nematodes. a potentially similar situation was disco ... | 2000 | 11155997 |
| in vitro activity of antimicrobial agents against the endosymbiont wolbachia pipientis. | arthropod-transmitted (filarial) nematodes are important causes of disease in humans in tropical countries, yet no safe drug appropriate for mass delivery kills the adult worms. however, most filarial nematodes contain rickettsia-like bacteria of the genus wolbachia, and related bacteria also occur in insects. there is increasing evidence that these bacteria have significant functions in the biology of filarial nematodes. they are thus important targets in the search for antifilarial drugs and e ... | 2001 | 11328780 |
| a newly discovered bacterium associated with parthenogenesis and a change in host selection behavior in parasitoid wasps. | the symbiotic bacterium wolbachia pipientis has been considered unique in its ability to cause multiple reproductive anomalies in its arthropod hosts. here we report that an undescribed bacterium is vertically transmitted and associated with thelytokous parthenogenetic reproduction in encarsia, a genus of parasitoid wasps. although wolbachia was found in only one of seven parthenogenetic encarsia populations examined, the "encarsia bacterium" (eb) was found in the other six. among seven sexually ... | 2001 | 11592990 |
| wolbachia density and virulence attenuation after transfer into a novel host. | the factors that control replication rate of the intracellular bacterium wolbachia pipientis in its insect hosts are unknown and difficult to explore, given the complex interaction of symbiont and host genotypes. using a strain of wolbachia that is known to over-replicate and shorten the lifespan of its drosophila melanogaster host, we have tracked the evolution of replication control in both somatic and reproductive tissues in a novel host/wolbachia association. after transinfection (the transf ... | 2002 | 11880639 |
| electron microscopic and molecular identification of wolbachia endosymbionts from onchocerca lupi: implications for therapy. | it was recently demonstrated that wolbachia intracellular bacteria (alpha 2 proteobacteria, rickettsiales) living in filarial nematodes are obligatory symbionts of their hosts. herein, we report the electron microscopic and 16s ribosomal dna-based (16s rdna) identification of the endobacteria harboring in onchocerca lupi. the worm nodules containing the nematodes were removed from three hungarian dogs naturally infected with o. lupi. wolbachia-like endobacteria were detected by electron microsco ... | 2002 | 11992713 |
| a host parasite interaction rescues drosophila oogenesis defects. | the cytoplasmically inherited bacterium wolbachia pipientis is a widespread parasite of arthropods that manipulates the reproductive biology of its hosts, often to their detriment, in order to foster its own transmission through egg cytoplasm. here we report that infection by wolbachia restores fertility to drosophila melanogaster mutant females prevented from making eggs by protein-coding lesions in sex-lethal (sxl), the master regulator of sex determination. suppression of sterility by wolbach ... | 2002 | 12097909 |
| host-symbiont conflicts: positive selection on an outer membrane protein of parasitic but not mutualistic rickettsiaceae. | the rickettsiaceae is a family of intracellular bacterial symbionts that includes both vertically transmitted parasites that spread by manipulating the reproduction of their host (wolbachia in arthropods) and horizontally transmitted parasites (represented by cowdria ruminantium), and mutualists (wolbachia pipientis in nematode worms). we have investigated the nature of natural selection acting on an outer membrane protein, the wsp gene in wolbachia and its homologue map1 in cowdria, thought lik ... | 2002 | 12140246 |
| within- and between-population variation for wolbachia-induced reproductive incompatibility in a haplodiploid mite. | wolbachia pipientis is a bacterium that induces cytoplasmic incompatibility (ci), the phenomenon in which infected males are reproductively incompatible with uninfected females. ci spreads in a population of hosts because it reduces the fitness of uninfected females relative to infected females. ci encompasses two steps: modification (mod) of sperm of infected males and rescuing (resc) of these chromosomes by wolbachia in the egg. infections associated with ci have mod+ resa+ phenotypes. however ... | 2002 | 12206235 |
| wolbachia distribution and cytoplasmic incompatibility during sperm development: the cyst as the basic cellular unit of ci expression. | the growth and distribution of the intracellular microbe wolbachia pipientis during spermatogenesis in several different host/symbiont genetic combinations in drosophila melanogaster and drosophila simulans is described. considerable intra- and inter-strain variation in wolbachia density and tissue distribution was observed. wolbachia were found inside spermatocytes and spermatids or within the somatic cyst cells surrounding the germ cells. some strains displayed both tissue distributions. high ... | 2003 | 12559491 |
| differences in extent of genetic introgression between sympatric culex pipiens and culex quinquefasciatus (diptera: culicidae) in california and south africa. | comparisons of five morphological characters, 12 enzyme electrophoresis profiles, and wolbachia pipientis infection rates were used to characterize populations of members of the culex pipiens l. complex in california and south africa. in south africa, male phallosome dv/d ratio, male maxillary palp index, branching of siphonal seta 1a, the enzyme locus mdhp-1, and w. pipientis infection rates proved highly diagnostic for separating culex quinquefasciatus from cx. pipiens phenotypes. in johannesb ... | 2003 | 12597651 |
| molecular detection of bartonella quintana, b. koehlerae, b. henselae, b. clarridgeiae, rickettsia felis, and wolbachia pipientis in cat fleas, france. | the prevalences of bartonella, rickettsia, and wolbachia were investigated in 309 cat fleas from france by polymerase chain reaction (pcr) assay and sequencing with primers derived from the glta gene for rickettsia, the its and pap31 genes for bartonella, and the 16s rrna gene for anaplasmataceae. positive pcr results were confirmed by using the lightcycler and specific primers for the rompb of rickettsia and glta of bartonella. r. felis was detected in 25 fleas (8.1%), w. pipientis, an insect s ... | 2003 | 12643829 |
| wolbachia pipientis growth kinetics and susceptibilities to 13 antibiotics determined by immunofluorescence staining and real-time pcr. | wolbachia spp. are strict intracellular bacteria that infect a wide range of arthropods and filarial nematodes. filarial nematodes are important causes of human diseases. there is increasing evidence that wolbachia spp. influence important functions in the biology of the hosts, specifically, infertility. preliminary experiments with humans and animals have suggested that antibiotics with activity against wolbachia may help to treat filariasis. in this study, we determined using a real-time quant ... | 2003 | 12709338 |
| rna polymerase beta-subunit-based phylogeny of ehrlichia spp., anaplasma spp., neorickettsia spp. and wolbachia pipientis. | sequence analysis of rpob, the gene encoding the beta-subunit of rna polymerase, was used in a phylogenetic investigation of nine species from the genera ehrlichia, neorickettsia, wolbachia and anaplasma. the complete nucleotide sequences obtained for anaplasma phagocytophilum (hge agent), ehrlichia chaffeensis, neorickettsia sennetsu, neorickettsia risticii, anaplasma marginale and wolbachia pipientis were amongst the longest rpob sequences in genbank and ranged from 4074 bp for n. sennetsu to ... | 2003 | 12710612 |
| endosymbiotic bacterium wolbachia pipientis in synanthropic populations of the mosquito culex pipiens pipiens l. (diptera, culicidae). | | 2003 | 12854423 |
| sperm chromatin remodelling and wolbachia-induced cytoplasmic incompatibility in drosophila. | wolbachia pipientis is an obligate bacterial endosymbiont, which has successfully invaded approximately 20% of all insect species by manipulating their normal developmental patterns. wolbachia-induced phenotypes include parthenogenesis, male killing, and, most notably, cytoplasmic incompatibility. in the future these phenotypes might be useful in controlling or modifying insect populations but this will depend on our understanding of the basic molecular processes underlying insect fertilization ... | 2003 | 12897857 |
| the distribution and evolutionary history of wolbachia infection in native and introduced populations of the invasive argentine ant (linepithema humile). | wolbachia pipientis is a maternally transmitted bacterium that often alters the life history of its insect host to maximize transmission to subsequent generations. here we report on the frequency and distribution of wolbachia infection in a widespread invasive species, the argentine ant (linepithema humile). we screened 1175 individual argentine ants from 89 nests on five continents and several islands, including numerous locations in both the native (south american) and introduced ranges. we de ... | 2003 | 14629385 |
| mitochondrial and wolbachia markers for the sandfly phlebotomus papatasi: little population differentiation between peridomestic sites and gerbil burrows in isfahan province, iran. | in iran, phlebotomus papatasi (scopoli) (diptera: psychodidae) is the main vector of leishmania major yakimoff & schokhor (kinetoplastida: trypanosomatidae), the causative agent of rural zoonotic cutaneous leishmaniasis. this sandfly is abundant both in villages and in the burrows of the main reservoir host, the gerbil rhombomys opimus (licht.) (rodentia: gerbillidae). populations of p. papatasi were sampled from the edges of villages in isfahan province, using cdc miniature light traps in perid ... | 2003 | 14651648 |
| culture and phenotypic characterization of a wolbachia pipientis isolate. | the recent isolation of wolbachia pipientis in the continuous cell line aa23, established from eggs of a strain of the asian tiger mosquito aedes albopictus, allowed us to perform extensive characterization of the isolate. bacterial growth could be obtained in c6/36, another a. albopictus cell line, at 28 degrees c and in a human embryonic lung fibroblast monolayer at 28 and 37 degrees c, confirming that its host cell range is broader than was initially thought. the bacteria were best visualized ... | 2003 | 14662922 |
| phylogenomics of the reproductive parasite wolbachia pipientis wmel: a streamlined genome overrun by mobile genetic elements. | the complete sequence of the 1,267,782 bp genome of wolbachia pipientis wmel, an obligate intracellular bacteria of drosophila melanogaster, has been determined. wolbachia, which are found in a variety of invertebrate species, are of great interest due to their diverse interactions with different hosts, which range from many forms of reproductive parasitism to mutualistic symbioses. analysis of the wmel genome, in particular phylogenomic comparisons with other intracellular bacteria, has reveale ... | 2004 | 15024419 |
| wolbachia pipientis: intracellular infection and pathogenesis in drosophila. | wolbachia pipientis is a vertically transmitted, obligate intracellular symbiont of arthropods. the bacterium is best known for its ability to manipulate host reproductive biology where it can induce cytoplasmic incompatibility, parthenogenesis, feminization and male-killing. in addition to the various reproductive phenotypes it generates through interaction with host reproductive tissue it is also known to infect somatic tissues. however, relatively little is known about the consequences of inf ... | 2004 | 15036143 |
| mapping the presence of wolbachia pipientis on the phylogeny of filarial nematodes: evidence for symbiont loss during evolution. | wolbachia pipientis is a bacterial endosymbiont associated with arthropods and filarial nematodes. in filarial nematodes, w. pipientis has been shown to play an important role in the biology of the host and in the immuno-pathology of filariasis. several species of filariae, including the most important parasites of humans and animals (e.g. onchocerca volvulus, wuchereria bancrofti and dirofilaria immitis) have been shown to harbour these bacteria. other filarial species, including an important r ... | 2004 | 15037105 |
| the sex ratio distortion in the human head louse is conserved over time. | at the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, pediculus humanus capitis, had been reported. a study by buxton in 1940 on the sex ratio of lice on prisoners in ceylon is still today the subject of reanalyses. this sex ratio distortion had been detected in ten different countries. in the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed ... | 2004 | 15140268 |
| dnaa gene sequences from wolbachia pipientis support subdivision into supergroups and provide no evidence for recombination in the lineages infecting nematodes. | wolbachia pipientis is an intracellular bacterial endosymbiont of arthropods and filarial nematodes. six main supergroups of w. pipientis have been described: supergroups a, b, e, and f encompass arthropod wolbachiae; supergroups c and d encompass nematode wolbachiae. the description of these six supergroups has been based on the analysis of only two genes (ftsz and 16s rdna) and before decisions are taken on the taxonomic status of the six supergroups, analysis of further genes is required. in ... | 2003 | 15270538 |
| wolbachia pipientis: symbiont or parasite? | | 1995 | 15275347 |
| wolbachia replication and host cell division in aedes albopictus. | wolbachia pipientis is an obligate intracellular endosymbiont of a range of arthropod species. the microbe is best known for its manipulations of host reproduction that include inducing cytoplasmic incompatibility, parthenogenesis, feminization, and male-killing. like other vertically transmitted intracellular symbionts, wolbachia's replication rate must not outpace that of its host cells if it is to remain benign. the mosquito aedes albopictus is naturally infected both singly and doubly with d ... | 2004 | 15297923 |
| variable fitness effects of wolbachia infection in drosophila melanogaster. | maternally inherited wolbachia bacteria are extremely widespread among insects and their presence is usually associated with parasitic modifications of host fitness. wolbachia pipientis infects drosophila melanogaster populations from all continents, but their persistence in this species occurs despite any strong parasitic effects. here, we have investigated the symbiosis between wolbachia and d. melanogaster and found that wolbachia infection can have significant survival and fecundity effects. ... | 2004 | 15305172 |
| wolbachia pipientis in australian spiders. | wolbachia pipientis is an endosymbiotic bacterium common to arthropods and filarial nematodes. this study presents the first survey and characterization of wolbachia pipientis that infect spiders. all spiders were collected from queensland, australia during 2002-2003 and screened for wolbachia infection using pcr approaches. the wolbachia strains present in the spiders are diverse, paraphyletic, and for the most part closely related to strains that infect insects. we have also identified several ... | 2004 | 15386106 |
| wolbachia infection in the newly described ecuadorian sand flea, tunga trimamillata. | wolbachia pipientis is an intracellular endosymbiont producing reproductive alterations in its hosts. this bacterium have been reported in many arthropods and nematodes. by pcr amplification and sequencing of the 16s rdna and ftsz genes we have identified a wolbachia strain in the newly described sand-flea, tunga trimamillata. prevalence of this endosymbiont in the 26 individuals screened is equal to 35%. sympatric and allopatric specimens of the related species tunga penetrans were also analyse ... | 2004 | 15491544 |
| distribution and diversity of wolbachia infections in southeast asian mosquitoes (diptera: culicidae). | wolbachia are a group of intracellular inherited bacteria that infect a wide range of arthropods. they are associated with a variety of reproductive alterations in their hosts, the best known being cytoplasmic incompatability. the wolbachia pipientis assemblage has been divided into two major groups (a and b) and 12 subgroups. we report herein the first systematic survey of wolbachia in mosquitoes, and the first survey classifying wolbachia infections by subgroup. wolbachia were detected in 28.1 ... | 2000 | 15535575 |
| detection and identification of ehrlichia spp. in ticks collected in tunisia and morocco. | a broad-range 16s rrna gene pcr assay followed by partial sequencing of the 16s rrna gene was used for the detection of members of the family anaplasmataceae in ticks in north africa. a total of 418 questing ixodes ricinus ticks collected in tunisia and morocco, as well as 188 rhipicephalus ticks from dogs and 52 hyalomma ticks from bovines in tunisia, were included in this study. of 324 adult i. ricinus ticks, 16.3% were positive for ehrlichia spp., whereas only 3.4 and 2.8% of nymphs and larva ... | 2005 | 15750072 |
| serendipitous discovery of wolbachia genomes in multiple drosophila species. | the trace archive is a repository for the raw, unanalyzed data generated by large-scale genome sequencing projects. the existence of this data offers scientists the possibility of discovering additional genomic sequences beyond those originally sequenced. in particular, if the source dna for a sequencing project came from a species that was colonized by another organism, then the project may yield substantial amounts of genomic dna, including near-complete genomes, from the symbiotic or parasiti ... | 2005 | 15774024 |
| [polymorphism of mitochondrial dna and infection with symbiotic cytoplasmic bacterium wolbachia pipientis in mosquitoes of the culex pipiens complex from russia]. | a total of 208 mosquitoes of the culex pipiens complex from 15 basement and terrestrial populations collected in different regions of the european part of russia and siberia were examined by genetic methods. among these, two major mitotypes, m and p, were identified. these mitotypes differed by six substitutions in the 246-bp mitochondrial dna cytochrome oxidase i gene fragment examined. urban basement mosquito ecotype c. pipiens (form molestus) were characterized by the presence of mitotype m a ... | 2005 | 15865286 |
| distribution, expression, and motif variability of ankyrin domain genes in wolbachia pipientis. | the endosymbiotic bacterium wolbachia pipientis infects a wide range of arthropods, in which it induces a variety of reproductive phenotypes, including cytoplasmic incompatibility (ci), parthenogenesis, male killing, and reversal of genetic sex determination. the recent sequencing and annotation of the first wolbachia genome revealed an unusually high number of genes encoding ankyrin domain (ank) repeats. these ank genes are likely to be important in mediating the wolbachia-host interaction. in ... | 2005 | 16030207 |
| can cytoplasmic incompatibility inducing wolbachia promote the evolution of mate preferences? | the maternally inherited bacterium, wolbachia pipientis, manipulates host reproduction by rendering uninfected females reproductively incompatible with infected males (cytoplasmic incompatibility, ci). hosts may evolve mechanisms, such as mate preferences, to avoid fitness costs of wolbachia infection. despite the potential importance of mate choice for wolbachia population dynamics, this possibility remains largely unexplored. here we model the spread of an allele encoding female mate preferenc ... | 2005 | 16033569 |
| evidence for a global wolbachia replacement in drosophila melanogaster. | wolbachia are maternally inherited intracellular alpha-proteobacteria found in numerous arthropod and filarial nematode species. they influence the biology of their hosts in many ways. in some cases, they act as obligate mutualists and are required for the normal development and reproduction of the host. they are best known, however, for the various reproductive parasitism traits that they can generate in infected hosts. these include cytoplasmic incompatibility (ci) between individuals of diffe ... | 2005 | 16085497 |
| [sexual reproduction of insects is regulated by cytoplasmic bacteria]. | the effects have been considered that the intracellular symbiotic alpha-proteobacteria wolbachia pipientis induces in its hosts, such as insects and other arthropods: cytoplasmic incompatibility upon mating, feminization, parthenogenesis, and androcide. specific features of the bacterium genome and possible mechanisms of its action on hosts are discussed. | 2005 | 16208939 |
| efficient procedure for purification of obligate intracellular wolbachia pipientis and representative amplification of its genome by multiple-displacement amplification. | bacteria belonging to the genus wolbachia are obligatory microendocytobionts that infect a variety of arthropods and a majority of filarial nematode species, where they induce reproductive alterations or establish a mutualistic symbiosis. although two whole genome sequences of wolbachia pipientis, for strain wmel from drosophila melanogaster and strain wbm from brugia malayi, have been fully completed and six other genome sequencing projects are ongoing (http://www.genomesonline.org/index.cgi?wa ... | 2005 | 16269725 |
| phylogeny of wolbachia pipientis based on glta, groel and ftsz gene sequences: clustering of arthropod and nematode symbionts in the f supergroup, and evidence for further diversity in the wolbachia tree. | current phylogenies of the intracellular bacteria belonging to the genus wolbachia identify six major clades (a-f), termed 'supergroups', but the branching order of these supergroups remains unresolved. supergroups a, b and e include most of the wolbachiae found thus far in arthropods, while supergroups c and d include most of those found in filarial nematodes. members of supergroup f have been found in arthropods (i.e. termites), and have previously been detected in the nematode mansonella ozza ... | 2005 | 16339946 |
| [differentiation between the urban mosquito culex pipiens pipiens f. molestus and culex torrentium (diptera: culicidae) by the molecular genetic methods]. | the molecular characters suitable for the differentiation between the autogenous form of culex pipiens pipiens (the urban mosquito) and the species culex torrentium, which was previously identified erroneously as an anautogenous form of c. pipiens pipiens (shaikevich, vinogradova, 2004), are given. these mosquitoes differ in the infection by the endosymbiotic bacteria wolbachia pipientis, 6 transitions among 247 nucleotide sequences of 3' part of the cytochrome oxidase subunit i (coi) gene of mi ... | 2005 | 16396396 |
| rate of elimination of wolbachia pipientis by doxycycline in vitro increases following drug withdrawal. | wolbachia pipientis is an obligate intracellular bacterium within the family anaplasmataceae that infects many terrestrial arthropods and arthropod-transmitted nematodes (filariae). several filarial species are major human pathogens, and antibiotics with activity against wolbachia offer a promising new therapeutic approach, since the adult worms are relatively refractory to conventional anthelmintics but depend on wolbachia for reproduction and viability. in a natural filarial parasite of cattle ... | 2006 | 16495252 |
| wolbachia infection reduces sperm competitive ability in an insect. | the maternally inherited bacterium wolbachia pipientis imposes significant fitness costs on its hosts. one such cost is decreased sperm production resulting in reduced fertility of male drosophila simulans infected with cytoplasmic incompatibility (ci) inducing wolbachia. we tested the hypothesis that wolbachia infection affects sperm competitive ability and found that wolbachia infection is indeed associated with reduced success in sperm competition in non-virgin males. in the second male role, ... | 2006 | 16777737 |
| wolbachia endosymbiotic bacteria of brugia malayi mediate macrophage tolerance to tlr- and cd40-specific stimuli in a myd88/tlr2-dependent manner. | lymphatic filarial nematodes are able to down-regulate parasite-specific and nonspecific responses of lymphocytes and apc. lymphatic filariae are reliant on wolbachia endosymbiotic bacteria for development and survival. we tested the hypothesis that repeated exposure to wolbachia endosymbionts would drive macrophage tolerance in vitro and in vivo. we pre-exposed murine peritoneal-elicited macrophages to soluble extracts of brugia malayi female worms (bmfe) before restimulating with bmfe or tlr a ... | 2006 | 16818783 |
| asymmetrical interactions between wolbachia and spiroplasma endosymbionts coexisting in the same insect host. | we investigated the interactions between the endosymbionts wolbachia pipientis strain wmel and spiroplasma sp. strain nsro coinfecting the host insect drosophila melanogaster. by making use of antibiotic therapy, temperature stress, and hemolymph microinjection, we established the following strains in the same host genetic background: the sw strain, infected with both spiroplasma and wolbachia; the s strain, infected with spiroplasma only; and the w strain, infected with wolbachia only. the infe ... | 2006 | 16820474 |
| f supergroup wolbachia in bush crickets: what do patterns of sequence variation reveal about this supergroup and horizontal transfer between nematodes and arthropods? | wolbachia pipientis, an intracellular, alpha-proteobacterium, is commonly found in arthropods and filarial nematodes. most infected insects are known to harbor strains of wolbachia from supergroups a or b, whereas supergroups c and d occur only in filarial nematodes. here, we present molecular evidence from two genes (ftsz and 16s rdna) that 2 orthopterans (the bush cricket species orocharis saltator and hapithus agitator; gryllidae: eneopterinae) are infected with wolbachia from the f supergrou ... | 2007 | 16924406 |
| feminizing wolbachia in zyginidia pullula (insecta, hemiptera), a leafhopper with an xx/x0 sex-determination system. | zyginidia pullula is a grass-dwelling leafhopper characterized by a bisexual reproduction mode. in this species, some females collected in northern italy, when mated with males, gave origin to an exclusively female brood. here, we demonstrated that in these lineages an infection by a new strain of wolbachia pipientis-designated as wzygpul-was detected by amplifying and sequencing the wsp and 16s rrna genes. about half of the female progeny were characterized by intersexual phenotypes, i.e. showi ... | 2006 | 16928646 |
| multilocus sequence typing system for the endosymbiont wolbachia pipientis. | the eubacterial genus wolbachia comprises one of the most abundant groups of obligate intracellular bacteria, and it has a host range that spans the phyla arthropoda and nematoda. here we developed a multilocus sequence typing (mlst) scheme as a universal genotyping tool for wolbachia. internal fragments of five ubiquitous genes (gatb, coxa, hcpa, fbpa, and ftsz) were chosen, and primers that amplified across the major wolbachia supergroups found in arthropods, as well as other divergent lineage ... | 2006 | 16936055 |
| survival of wolbachia pipientis in cell-free medium. | wolbachia pipientis is an obligate intracellular bacterium found in a wide range of invertebrate taxa. while over ecological timescales wolbachia infections are maintained by strict maternal inheritance, horizontal transfer events are common over evolutionary time. to be horizontally transferred between organisms, wolbachia bacteria must pass through and survive an extracellular phase. we used baclight live-dead staining, pcr, and fluorescence in situ hybridization to assess the ability for puri ... | 2006 | 16950898 |
| can anopheles gambiae be infected with wolbachia pipientis? insights from an in vitro system. | wolbachia pipientis are maternally inherited endosymbionts associated with cytoplasmic incompatibility, a potential mechanism to drive transgenic traits into anopheles populations for malaria control. w. pipientis infections are common in many mosquito genera but have never been observed in any anopheles species, leading to the hypothesis that anopheles mosquitoes are incapable of harboring infection. we used an in vitro system to evaluate the ability of anopheles gambiae cells to harbor diverse ... | 2006 | 17028229 |
| toward a wolbachia multilocus sequence typing system: discrimination of wolbachia strains present in drosophila species. | among the diverse maternally inherited symbionts in arthropods, wolbachia are the most common and infect over 20% of all species. in a departure from traditional genotyping or phylogenetic methods relying on single wolbachia genes, the present study represents an initial multilocus sequence typing (mlst) analysis to discriminate closely related wolbachia pipientis strains, and additional data on sequence diversity in wolbachia. we report a new phylogenetic characterization of four genes (aspc, a ... | 2006 | 17036209 |
| increased male mating rate in drosophila is associated with wolbachia infection. | the maternally inherited bacterium wolbachia pipientis infects 25-75% of arthropods and manipulates host reproduction to improve its transmission. one way wolbachia achieves this is by inducing cytoplasmic incompatibility (ci), where crosses between infected males and uninfected females are inviable. infected males suffer reduced fertility through ci and reduced sperm production. however, wolbachia induce lower levels of ci in nonvirgin males. we examined the impact of wolbachia on mating behavi ... | 2006 | 17040394 |
| disruption of the wolbachia surface protein gene wspb by a transposable element in mosquitoes of the culex pipiens complex (diptera, culicidae). | culex pipiens quinquefasciatus say and culex pipiens pipiens linnaeus are sibling species incriminated as important vectors of emerging and re-emerging infectious diseases worldwide. the two forms differ little morphologically and are differentiated mainly based upon ecological, behavioural, physiological and genetic traits. within the north american zone of sympatry, populations of cx. p. quinquefasciatus and cx. p. pipiens undergo extensive introgression and hybrid forms have been reported in ... | 2007 | 17298560 |
| taxonomic status of the intracellular bacterium wolbachia pipientis. | wolbachia pipientis is a maternally inherited, intracellular bacterium found in more than 20 % of all insects, as well as numerous other arthropods and filarial nematodes. it has been the subject of a growing number of studies in recent decades, because of the remarkable effects it has on its arthropod hosts, its potential as a tool for biological control of arthropods of agricultural and medical importance and its use as a target for treatment of filariasis. w. pipientis was originally discover ... | 2007 | 17329802 |
| genetic diversity of costa rican populations of the rice planthopper tagosodes orizicolus (homoptera: delphacidae). | tagosodes orizicolus (homoptera: delphacidae) is one of the main constraints of the rice production in the neotropics. this planthopper produces severe damages as a phloem feeder, causes mechanical injury during oviposition and vectors the rice hoja blanca virus (rhbv). the main objective of this study was to determine the genetic diversity of t. orizicolus populations from three rice growing regions of costa rica, using rapds. individuals from guanacaste, parrita, san carlos and cali-colombia, ... | 2004 | 17361572 |
| diversifying selection and host adaptation in two endosymbiont genomes. | the endosymbiont wolbachia pipientis infects a broad range of arthropod and filarial nematode hosts. these diverse associations form an attractive model for understanding host:symbiont coevolution. wolbachia's ubiquity and ability to dramatically alter host reproductive biology also form the foundation of research strategies aimed at controlling insect pests and vector-borne disease. the wolbachia strains that infect nematodes are phylogenetically distinct, strictly vertically transmitted, and r ... | 2007 | 17470297 |
| new criteria for selecting the origin of dna replication in wolbachia and closely related bacteria. | the annotated genomes of two closely related strains of the intracellular bacterium wolbachia pipientis have been reported without the identifications of the putative origin of replication (ori). identifying the ori of these bacteria and related alpha-proteobacteria as well as their patterns of sequence evolution will aid studies of cell replication and cell density, as well as the potential genetic manipulation of these widespread intracellular bacteria. | 2007 | 17584494 |
| on the taxonomic status of the intracellular bacterium wolbachia pipientis: should this species name include the intracellular bacteria of filarial nematodes? | | 2007 | 17684235 |
| widespread lateral gene transfer from intracellular bacteria to multicellular eukaryotes. | although common among bacteria, lateral gene transfer-the movement of genes between distantly related organisms-is thought to occur only rarely between bacteria and multicellular eukaryotes. however, the presence of endosymbionts, such as wolbachia pipientis, within some eukaryotic germlines may facilitate bacterial gene transfers to eukaryotic host genomes. we therefore examined host genomes for evidence of gene transfer events from wolbachia bacteria to their hosts. we found and confirmed tran ... | 2007 | 17761848 |
| anthraquinones as defensive compounds in eggs of galerucini leaf beetles: biosynthesis by the beetles? | eggs of leaf beetles of the tribe galerucini, subfamily galerucinae, contain polyketides that are unusual in insects: 1,8-dihydroxylated anthraquinones (chrysazin, chrysophanol) and anthrones (dithranol, chrysarobin) deterring predators. the host plants do not contain these compounds. in the present study, we tested the hypothesis that the beetles, but not bacterial or fungal microorganisms living as endosymbionts within the beetles, produce the anthraquinones. the tansy leaf beetle galeruca tan ... | 2007 | 17879233 |
| symbiont genes in host genomes: fragments with a future? | while lateral transfer is the rule in the evolutionary history of bacterial and archaeal genes, events of transfer from prokaryotes to eukaryotes are rare. germline-transmitted animal symbionts, such as wolbachia pipientis, are well placed to participate in such transfers. in a recent issue of science, dunning hotopp et al. identified instances of transfer of wolbachia dna to host genomes. it is unknown whether these transfers represent innovation in animal evolution. | 2007 | 18005738 |
| iswpi1 from wolbachia pipientis defines a novel group of insertion sequences within the is5 family. | insertion sequences are transposable elements that can represent substantial proportions of prokaryotic genomes and play a substantial role in shaping host genome evolution. as such, evaluating and understanding insertion sequence diversity is an important task to fulfill, because it is expected to yield new insight into the evolution of bacterial transposable elements and contribute to improve genome annotations. here, i characterized an insertion sequence, termed iswpi1, for which the taxonomi ... | 2008 | 18155858 |
| [evolution from retrotransposons to retroviruses: origin of the env gene]. | in genome of drosophila melanogaster, various families of retrotransposons with different combination of functional domens and mechanisms of transposition are present. however only retrotransposons of gypsy family are retroviruses related to errantiviruses. other families seemingly appeared as intermediate forms of retroviruses evolution. despite the fact that the question on origin of retroviruses remains unclear, now the hypothesis of their origin from retrotransoposons can be considered the m ... | 2007 | 18257289 |
| crystallization and preliminary diffraction analysis of a dsba homologue from wolbachia pipientis. | alpha-dsba1 is one of two dsba homologues encoded by the gram-negative alpha-proteobacterium wolbachia pipientis, an endosymbiont that can behave as a reproductive parasite in insects and as a mutualist in medically important filarial nematodes. the alpha-dsba1 protein is thought to be important for the folding and secretion of wolbachia proteins involved in the induction of reproductive distortions. crystals of native and semet alpha-dsba1 were grown by vapour diffusion and belong to the monocl ... | 2008 | 18259058 |
| diversity of ixodes ricinus tick-associated bacterial communities from different forests. | nymphal ixodes ricinus ticks (n=180) were collected from three different areas in the netherlands to investigate the effect of forest composition on tick-associated microbial communities. sampled habitats differed in thickness of leaf litter and humus layers and vegetation associations and were located near amsterdam (beech-oak), ede (birch-oak) and veldhoven (birch-oak). analysis of nine 16s rrna gene clone libraries made from individual ticks showed nearest matches with presumed pathogens cand ... | 2008 | 18355299 |
| cloning, expression, purification and characterization of a dsba-like protein from wolbachia pipientis. | wolbachia pipientis are obligate endosymbionts that infect a wide range of insect and other arthropod species. they act as reproductive parasites by manipulating the host reproduction machinery to enhance their own transmission. this unusual phenotype is thought to be a consequence of the actions of secreted wolbachia proteins that are likely to contain disulfide bonds to stabilize the protein structure. in bacteria, the introduction or isomerization of disulfide bonds in proteins is catalyzed b ... | 2008 | 18387819 |
| cytological properties of an aedes albopictus mosquito cell line infected with wolbachia strain walbb. | in vitro production of the obligate intracellular bacterium, wolbachia pipientis, is essential to its manipulation as a genetic tool to spread transgenes within vector populations. we have adapted the wolbachia-infected aa23 aedes albopictus mosquito cell line to eagle's minimal medium, supplemented with nonessential amino acids, glutamine, and 20% fetal bovine serum. when plated at low densities, aa23e cells grew as patchy monolayers, comprised of non-contiguous clusters of cells that gave rise ... | 2008 | 18401667 |
| molecular and functional characterization of granulin-like molecules of insects. | granulins are a group of highly conserved growth factors that have been described from a variety of organisms spanning the metazoa. here, we report on the identification of two partial transcripts encoding granulin-like molecules from aa23 embryonic cells of aedes albopictus and primary haemocytes from manduca sexta. both these partial transcripts had the characteristic 12-cysteine motif that is a hallmark of the granulin family and they represent the first granulin mrna transcripts identified f ... | 2008 | 18405836 |
| wolbachia infection alters olfactory-cued locomotion in drosophila spp. | wolbachia pipientis is an endosymbiotic bacterium present in diverse insect species. although it is well studied for its dramatic effects on host reproductive biology, little is known about its effects on other aspects of host biology, despite its presence in a wide array of host tissues. this study examined the effects of three wolbachia strains on two different drosophila species, using a laboratory performance assay for insect locomotion in response to olfactory cues. the results demonstrate ... | 2008 | 18456851 |
| the endosymbiont wolbachia pipientis induces the expression of host antioxidant proteins in an aedes albopictus cell line. | wolbachia are obligate intracellular bacteria which commonly infect arthropods. they are maternally inherited and capable of altering host development, sex determination, and reproduction. reproductive manipulations include feminization, male-killing, parthenogenesis, and cytoplasmic incompatibility. the mechanism by which wolbachia avoid destruction by the host immune response is unknown. generation of antimicrobial peptides (amps) and reactive oxygen species (ros) by the host are among the fir ... | 2008 | 18461124 |