Publications

wolbachia-induced delay of paternal chromatin condensation does not prevent maternal chromosomes from entering anaphase in incompatible crosses of drosophila simulans.	the behavior of parental chromosomes during the first mitosis of drosophila simulans zygotes obtained from unidirectional incompatible crosses is described and it is demonstrated that the condensation of parental chromatin complements was asynchronous. the timing of paternal chromatin condensation appeared to be delayed in these embryos, so that condensed maternal chromosomes and entangled prophase-like paternal fibers congressed in the equatorial plane of the first metaphase spindle. at anaphas ...	1997	9044057
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
reduced variation in drosophila simulans mitochondrial dna.	we investigated the evolutionary dynamics of infection of a drosophila simulans population by a maternally inherited insect bacterial parasite, wolbachia, by analyzing nucleotide variability in three regions of the mitochondrial genome in four infected and 35 uninfected lines. mitochondrial variability is significantly reduced compared to a noncoding region of a nuclear-encoded gene in both uninfected and pooled samples of flies, indicating a sweep of genetic variation. the selective sweep of mi ...	1996	8978041
wolbachia infection and cytoplasmic incompatibility in drosophila species.	forty-one stocks from 30 drosophila species were surveyed for wolbachia infection using pcr technology. d. sechellia and two strains of d. auraria were found to be infected and were tested for the expression of cytoplasmic incompatibility, along with d. ananassae and d. melanogaster strains, which are already known to be infected. d. ananassae and d. melanogaster show levels of incompatibility up to 25%, while d. auraria and d. sechellia exhibit levels of egg mortality approximately 60%. a dot-b ...	1996	8913750
wolbachia: intracellular manipulators of mite reproduction.	cytoplasmically transmitted wolbachia (alpha-proteobacteria) are a group of closely related intracellular microorganisms that alter reproduction in arthropods. they are found in a few isopods and are widespread in insects. wolbachia are implicated as the cause of parthenogenesis in parasitic wasps, feminization in isopods and reproductive (cytoplasmic) incompatibility in many insects. here we report on the widespread occurrence of wolbachia in spider mites and predatory mites based on a pcr assa ...	1996	8856963
pcr-based detection of wolbachia, cytoplasmic incompatibility microorganisms, infected in natural populations of laodelphax striatellus (homoptera: delphacidae) in central japan: has the distribution of wolbachia spread recently?	cytoplasmic incompatibility is caused in various insects by intracellular infection with rickettsia-like microorganisms of the genus wolbachia. in japan laodelphax striatellus shows unidirectional cytoplasmic incompatibility between northeastern and southwestern populations. in this study, nine natural populations of l. striatellus collected from central japan, including the geographic boundary between the two cytotype populations, were analysed for wolbachia infection by pcr using primers speci ...	1995	8825761
cytological analysis of fertilization and early embryonic development in incompatible crosses of drosophila simulans.	cytoplasmic incompatibility (ci) is a unique form of male sterility found in numerous insect species that harbor a bacterial endosymbiont wolbachia. ci is characterized by severe reduction in the progeny produced when infected males are crossed to uninfected females. the reduction in progeny correlates with developmental defects that arise during and immediately following fertilization, suggesting that sperm function is disrupted. to investigate the nature of the cellular defects associated with ...	1996	8817452
molecular identification of a wolbachia endosymbiont in a tetranychus urticae strain (acari: tetranychidae).	wolbachia, a maternally inherited bacterium, is involved in alterations of arthropod sexuality. reproductive incompatibilities are often observed in miles, but the existence of this microorganism in their cytoplasm has not yet been demonstrated. we identified the presence of wolbachia in a strain of the spider mite tetranychus urticae based on the amplification and sequencing of part of the 16s rdna and ftsz genes. in order to establish the phylogenetic relationships between wolbachia found in t ...	1996	8799741
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
single and double infections with wolbachia in the parasitic wasp nasonia vitripennis: effects on compatibility.	wolbachia are cytoplasmically inherited bacteria responsible for reproductive incompatibility in a wide range of insects. there has been little exploration, however, of within species wolbachia polymorphisms and their effects on compatibility. here we show that some strains of the parasitic wasp nasonia vitripennis are infected with two distinct bacterial strains (a and b) whereas others are singly infected (a or b). double and single infections are confirmed by both pcr amplification and southe ...	1996	8725242
molecular evidence for a close relative of the arthropod endosymbiont wolbachia in a filarial worm.		1995	8719164
parthenogenesis-inducing microorganisms in aphytis (hymenoptera: aphelinidae).	production of males in uniparental lines of two species in the parasitic wasp genus aphytis was induced by rifampicin, and male sexual functioning was determined. wolbachia-specific 16s rdna primers were used in a pcr in order to: (1) assess correlation between thelytokous reproduction and the presence of wolbachia; (2) detect the loss of wolbachia dna in uniparental a. lingnanensis following antibiotic treatments, with or without the presence of a host; and (3) clone and sequence part of the wo ...	1995	8589844
wolbachia superinfections and the expression of cytoplasmic incompatibility.	strains of drosophila simulans from riverside, california (dsr) and hawaii (dsh) harbour distinct strains of the cytoplasmic incompatibility microorganism wolbachia, resulting in the expression of bidirectional incompatibility when crossed. d. simulans lines carrying both of these (superinfected) wolbachia strains were generated by the transfer of infected dsh cytoplasm into dsr embryos by microinjection. the superinfected flies were unidirectionally incompatible with both dsr and dsh individual ...	1995	8587875
variability within the seychelles cytoplasmic incompatibility system in drosophila simulans.	in drosophila simulans, we described a cytoplasmic incompatibility (ci) system (seychelles) restricted to insular populations that harbor the mitochondrial type sii. since then, these populations have been shown to be heterogeneous, some being infected by one wolbachia genetic variant only (wha), while others are infected simultaneously by wha and by another variant (wno) always found in association with wha. we have experimentally obtained two d. simulans strains only infected by the wno varian ...	1995	8582608
naturally-occurring wolbachia infection in drosophila simulans that does not cause cytoplasmic incompatibility.	microbes of the genus wolbachia are transmitted by their hosts via the maternal parent and are responsible for cytoplasmic incompatibility among insect populations. this phenomenon can result in wolbachia spreading through natural populations as previously demonstrated in drosophila simulans. here we describe another wolbachia infection in d. simulans that does not cause cytoplasmic incompatibility. this is a property of the wolbachia rather than the nuclear background. the infection occurs at a ...	1996	8575931
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
interspecific and intraspecific horizontal transfer of wolbachia in drosophila.	cytoplasmic incompatibility (ci) in drosophila simulans is related to infection of the germ line by a rickettsial endosymbiont (genus wolbachia). wolbachia were transferred by microinjection of egg cytoplasm into uninfected eggs of both d. simulans and d. melanogaster to generate infected populations. transinfected strains of d. melanogaster with lower densities of wolbachia than the naturally infected d. simulans strain did not express high levels of ci. however, transinfected d. melanogaster e ...	1993	8511587
ultrastructure of spotted fever rickettsialike microorganisms observed in tissues of dermacentor taiwanensis (acari: ixodidae).	tissues of midguts, malpighian tubules, salivary glands, and ovaries of female dermacentor taiwanensis sugimoto collected in an area endemic for japanese spotted fever were examined with an electron microscope, and the presence of two kinds of rickettsialike microorganisms was confirmed in japan. based on ultrastructural findings, a rod-shaped organism detected in all the tissues is a rickettsia; another, irregularly shaped organism that was found only in the ovary, is a wolbachia. a hemolymph t ...	1993	8510117
conflict between feminizing sex ratio distorters and an autosomal masculinizing gene in the terrestrial isopod armadillidium vulgare latr.	female sex determination in the pill bug armadillidium vulgare is frequently under the control of feminizing parasitic sex factors (psf). one of these psf is an intracytoplasmic wolbachia-like bacterium (f), while the other (f) is suspected of being an f-bacterial dna sequence unstably integrated into the host genome. in most wild populations harboring psf, all individuals are genetic males (zz), and female phenotypes occur only due to the presence of psf which overrides the male determinant car ...	1993	8436273
phylogenetically distant symbiotic microorganisms reside in glossina midgut and ovary tissues.	many blood-feeding insects, including tsetse flies (diptera: glossinidae), harbour intracellular bacterial symbionts. using isolates from tissues of several glossina species and diagnostic dna oligonucleotide primers, a polymerase chain reaction (pcr) based assay was designed to identify symbiotic bacteria. those inhabiting the midgut of glossina were found to belong to the gamma subdivision, whereas ovarian proteobacteria were of the alpha subdivision--probably genus wolbachia (rickettsiaceae). ...	1993	8268495
properties of drosophila simulans strains experimentally infected by different clones of the bacterium wolbachia.	maternally inherited bacteria of the genus wolbachia are responsible for reproductive incompatibilities between strains of drosophila simulans. such incompatibilities are known in several types of crosses, including both directions of crossing between two types of infected strains, 'r' and 's'. to determine whether the bidirectional incompatibility between r and s flies is due only to differences between their bacteria, flies from an uninfected strain have been experimentally infected with bacte ...	1994	8200813
mitochondrial dna polymorphism and feminizing sex factors dynamics in a natural population of armadillidium vulgare (crustacea, isopoda).	sex determination in armadillidium vulgare may be under the control of two parasitic sex factors that reverse genetic males into functional neo-females. the first feminizing factor (f) is a wolbachia and the other (f) is probably a sequence of the f bacterial dna unstably integrated into the host genome. both of these feminizing factors are mainly maternally transmitted. here we investigate the mitochondrial dna polymorphism of wild iso-female lineages harbouring either f or f. among the four ha ...	1993	8163156
analysis of 16s ribosomal dna sequences of francisella strains and utilization for determination of the phylogeny of the genus and for identification of strains by pcr.	the 16s ribosomal dnas (rdnas) of two strains of francisella tularensis and one strain of francisella philomiragia were sequenced. on the basis of phylogenetic analysis data, the genus francisella was placed in the gamma subclass of the proteobacteria. the most closely related organism was the intracellular bacterium wolbachia persica. the sequenced 16s rdna molecules of the francisella species exhibited very high levels of similarity (98.5 to 99.9%). two variable regions, comprising 390 to 450 ...	1994	8123561
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
endosymbiotic relationship between a rickettsia-like microorganism and the male germ-cells of culex tigripes.	the male mosquitoes of the species culex tigripes possess endosymbionts localized in the cytoplasm of the germ-cells. the somatic cells of the testis do not exhibit this particularity. the spermatogonia, spermatocytes and spermatids all possess a few symbionts. they are eliminated in the residual body at the end of spermiogenesis when the spermatozoon matures. they are absent from the seminal vesicles. a few spermatocytes and spermatids show a proliferation of the endosymbionts. this seems to be ...	1993	8096432
cytoplasmic incompatibility in australian populations of drosophila melanogaster.	in drosophila melanogaster, weak incompatibility in crosses between infected and uninfected strains is associated with a wolbachia microorganism. crosses between infected males and uninfected females show a reduction (15-30%) in egg hatch. progeny tests indicated that the infection is widespread in australian d. melanogaster populations and that populations are polymorphic for the presence of the infection. the infection status of 266 lines from 12 populations along the eastern coast of australi ...	1994	8005448
diversity within diversity: molecular approaches to studying microbial interactions with insects.	dna sequence information has greatly augmented the number of characters available for analysis in phylogenetic research. nowhere is this more evident than in studies of microbial evolution. ribosomal dna sequence data has simultaneously permitted the distinction between individual species and the inference of their phylogenetic relationships in many cases where both were formerly impossible. these have contributed to our understanding of the ecology of particular microbe-host interactions and th ...	1994	7994122
the effect of population subdivision on the rate of spread of parasite-mediated cytoplasmic incompatibility.	over 20 species of arthropods are known to harbor an endosymbiotic bacterium, wolbachia associated with partial reproductive incompatibility. the micro-organism spreads through a random mating population with positive frequency dependence. many insect populations, however, are subdivided to some degree. in this paper we model the effect of population subdivision on the rate of spread of wolbachia and show that it slows the rate of spread of the micro-organism but by itself cannot cause a stable ...	1994	7909859
replacement of the natural wolbachia symbiont of drosophila simulans with a mosquito counterpart.	inherited rickettsial symbionts of the genus wolbachia occur commonly in arthropods and have been implicated in the expression of parthenogenesis, feminization and cytoplasmic incompatibility wolbachia from the asian tiger mosquito, aedes albopictus, to replace the natural infection of drosophila simulans by means of embryonic microinjection techniques. the transferred wolbachia infection behaves like a natural drosophila infection with regard to its inheritance, cytoskeleton interactions and ab ...	1994	7906391
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
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
evidence for a wolbachia symbiont in drosophila melanogaster.	the bacterial cell division gene, ftsz, was used as a specific probe to show the presence of a symbiotic bacterium in two wild type strains of drosophila melanogaster. under stringent hybridization conditions we have shown that the bacterium is transferred to the progeny of these strains from infected mothers and can be eradicated by treatment with the antibiotic tetracycline. we have characterized this bacterium, by amplifying and sequencing its 16s rrna gene, as being a member of the genus wol ...	1993	7691685
the reproductive incompatibility system in drosophila simulans: dapi-staining analysis of the wolbachia symbionts in sperm cysts.	any hitherto available technique used to detect the presence of wolbachia, a rickettsia-like endosymbiont of drosophila simulans, i.e., crossing with tester strains, electron microscope observations, dapi-staining of embryo, or amplification of specific sequences by pcr are notably time-consuming techniques. staining sperm cysts with the fluorochrome dapi is here shown to be a fast and reliable technique to detect the symbiont and evaluate the level of infection of individual males. wolbachia ce ...	1993	7689622
cloning and characterization of an ftsz homologue from a bacterial symbiont of drosophila melanogaster.	a 1194 bp open reading frame that codes for a 398 amino acid peptide was cloned from a lambda gt11 library of drosophila melanogaster genomic dna. the predicted peptide sequence is very similar to three previously characterized protein sequences that are encoded by the ftsz genes in escherichia coli, bacillus subtilis and rhizobium meliloti. the ftsz protein has a major role in the initiation of cell division in prokaryotic cells. using a tetracycline treatment that eradicates bacterial parasite ...	1993	7689140
evolution and phylogeny of wolbachia: reproductive parasites of arthropods.	wolbachia are cytoplasmically inherited bacteria found in reproductive tissues of many arthropod species. these bacteria are associated with reproductive alterations in their hosts, including parthenogenesis, reproductive incompatibility and feminization. a fine-scale phylogenetic analysis was done using dna sequences from ftsz, a rapidly evolving bacterial cell-cycle gene. ftsz sequences were determined for 38 different wolbachia strains from 31 different species of insects and one isopod. the ...	1995	7644549
evolution of single and double wolbachia symbioses during speciation in the drosophila simulans complex.	maternally inherited bacteria of the genus wolbachia are responsible for the early death of embryos in crosses between uninfected females and infected males in several insect species. this phenomenon, known as cytoplasmic incompatibility, also occurs between strains infected by different symbionts in some species, including drosophila simulans. wolbachia was found in two species closely related to d. simulans, drosophila mauritiana, and drosophila sechellia, and shown to cause incompatibility in ...	1995	7604001
induction of paternal genome loss by the paternal-sex-ratio chromosome and cytoplasmic incompatibility bacteria (wolbachia): a comparative study of early embryonic events.	paternal genome loss (pgl) during early embryogenesis is caused by two different genetic elements in the parasitoid wasp, nasonia vitripennis. paternal sex ratio (psr) is a paternally inherited supernumerary chromosome that disrupts condensation of the paternal chromosomes by the first mitotic division of fertilized eggs. bacteria belonging to the genus wolbachia are present in nasonia eggs and also disrupt paternal chromosome condensation in crosses between cytoplasmically incompatible strains. ...	1995	7598906
wolbachia and cytoplasmic incompatibility in mycophagous drosophila and their relatives.	bacterial symbionts belonging to the genus wolbachia are associated with postzygotic reproductive incompatibility in a number of insect species. using polymerase chain reaction (pcr) amplification of bacterial gene sequences, strains from 10 species belonging to the closely related quinaria, testacea and tripunctata groups of drosophila were screened for the presence of wolbachia in their reproductive tissues. those screened included the mycophagous species d. falleni, d. recens, d. phalerata, d ...	1995	7558891
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
cytoplasmic incompatibility in drosophila simulans: dynamics and parameter estimates from natural populations.	in drosophila simulans, cytoplasmically transmitted wolbachia microbes cause reduced egg hatch when infected males mate with uninfected females. a wolbachia infection and an associated mtdna variant have spread northward through california since 1986. pcr assays show that wolbachia infection is prevalent throughout the continental us and central and south america, but some lines from florida and ecuador that are pcr-positive for wolbachia do not cause incompatibility. we estimate from natural po ...	1995	7498773
wolbachia infections and the expression of cytoplasmic incompatibility in drosophila sechellia and d. mauritiana.	various stocks of drosophila mauritiana and d. sechellia were found to be infected with wolbachia, a rickettsia-like bacterium that is known to cause cytoplasmic incompatibility and other reproductive abnormalities in arthropods. testing for the expression of cytoplasmic incompatibility in these two species showed partial incompatibility in d. sechellia but no expression of incompatibility in d. mauritiana. to determine whether absence of cytoplasmic incompatibility in d. mauritiana was due to e ...	1995	7498772
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
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
the ultrastructure and symbiotic relationships of wolbachia of mosquitoes of the aedes scutellaris group.		1980	7411685
a rickettsia-like microorganism similar to wolbachia pipientis and its occurrence in culex mosquitoes.		1983	6863975
reproduction of an inbred strain of culex pipiens prevented by loss of wolbachia pipientis.		1983	6404990
rickettsiaceae and chlamydiaceae: comparative electron microscopic studies.	the structure and cytopathology of obligate intracellular bacteria belonging to families rickettsiaceae and chlamydiaceae and their interaction with eukaryotic host cells were compared in electron microscopic studies. "rickettsia-like" and "chlamydia-like" types of organization of bacterial cells and their interaction with host cells are presented. the rickettsia-like type is characterized by short rod-shaped cells multiplying freely ( extravacuolarly ) in the cytoplasm or nucleoplasm of the hos ...	1984	6145350
fine structure of the vagina, accessory glands, uterus, oviducts and gene's organ in the unfed tick, ornithodoros (pavlovskyella) erraticus (ixodoidea: argasidae).	the fine structure of the reproductive system of the unfed female ornithodoros (pavloskyella) erraticus is described. the vagina consisting of vestibular (vv) and cervical (cv) regions is formed of a single epithelial layer lined with cuticle and surrounded by muscle layers. epithelial cells of vv show no signs of activity, while those of cv have structural features of transporting epithelia. a pair of tubular accessory glands opening at the junction of the two vaginal regions consist of a layer ...	1988	3409790
phylogenetic diversity of the rickettsiae.	small subunit rrna sequences have been determined for representative strains of six species of the family rickettsiaceae: rickettsia rickettsii, rickettsia prowazekii, rickettsia typhi, coxiella burnetii, ehrlichia risticii, and wolbachia persica. the relationships among these sequences and those of other eubacteria show that all members of the family rickettsiaceae belong to the so-called purple bacterial phylum. the three representatives of the genus rickettsia form a tight monophyletic cluste ...	1989	2753854
factors affecting the distribution of cytoplasmic incompatibility in drosophila simulans.	in drosophila simulans a wolbachia-like microorganism is responsible for reduced egg-hatch when infected males mate with uninfected females. both incompatibility types have previously been found in north america, europe and africa. some california populations have remained polymorphic for over two years, and the infection is apparently spreading in central california. egg hatch proportions for wild-caught females from polymorphic populations show that the incompatibility system acts in nature, b ...	1990	2076821
geographic distribution and inheritance of three cytoplasmic incompatibility types in drosophila simulans.	wolbachia-like microorganisms have been implicated in unidirectional cytoplasmic incompatibility between strains of drosophila simulans. reduced egg eclosion occurs when females from uninfected strains (type w) are crossed with males from infected strains (type r). here we characterize a third incompatibility type (type s) which is also correlated with the presence of wolbachia-like microorganisms. despite the fact that the symbionts cannot be morphologically distinguished, we observed complete ...	1991	1743484
16s rrna phylogenetic analysis of the bacterial endosymbionts associated with cytoplasmic incompatibility in insects.	bacterial endosymbionts of insects have long been implicated in the phenomenon of cytoplasmic incompatibility, in which certain crosses between symbiont-infected individuals lead to embryonic death or sex ratio distortion. the taxonomic position of these bacteria has, however, not been known with any certainty. similarly, the relatedness of the bacteria infecting various insect hosts has been unclear. the inability to grow these bacteria on defined cell-free medium has been the major factor unde ...	1992	1557375
piscirickettsia salmonis gen. nov., sp. nov., the causative agent of an epizootic disease in salmonid fishes.	a novel intracellular pathogen morphologically similar to the ehrlichiae has been isolated in cell culture and identified as the cause of an epizootic disease of salmonid fish. like the ehrlichiae, the salmonid pathogen, designated strain lf-89, replicates within membrane-bound cytoplasmic vacuoles in host cells. this agent is the first with characteristics of this type to be isolated from a fish. analysis of the lf-89 16s rrna indicated that, unlike the ehrlichiae, lf-89 is a gamma proteobacter ...	1992	1371057
wolbachia endosymbionts responsible for various alterations of sexuality in arthropods.	rickettsia-like maternally inherited bacteria have been shown to be involved in a variety of alterations of arthropod sexuality, such as female-biased sex ratios, parthenogenesis, and sterility of crosses either between infected males and uninfected females or between infected individuals (cytoplasmic incompatibility). we have characterized several of these microorganisms through partial sequences of the small (16s) and large (23s) subunit ribosomal dna. all the symbionts identified, which inclu ...	1992	1361987
molecular identification of wolbachia, the agent of cytoplasmic incompatibility in drosophila simulans, and variability in relation with host mitochondrial types.	sequences of a segment of the 16s ribosomal dna of wolbachia, a rickettsia-like microorganism responsible for cytoplasmic incompatibility in drosophila simulans, have been obtained after polymerase chain reaction (pcr) amplification. their comparison with other eubacterial sequences allows us to assign these endosymbionts to the alpha subdivision of purple bacteria. four related sequences have been obtained for microorganisms carried by eight isofemale lines representative of the three mitochond ...	1992	1350096
"curing" wolbachia infections in culex pipiens.		1975	808618
the ultrastructure of the rickettsia-like microorganism wolbachia pipientis and associated virus-like bodies in the mosquito culex pipiens.		1978	671578
electronmicroscopic investigations of wolbachia-like microorganisms in haemaphysalis inermis.		1977	600395
isolation of spotted fever group and wolbachia-like agents from field-collected materials by means of plaque formation in mammalian and mosquito cells.	three isolations from ticks (dermacentor occidentalis) of a rickettsia of the spotted fever group and 5 isolations from chipmunk (eutamias rugicaudus) blood of a wolbachia-like agent were obtained from plaques formed in singh's aedes albopictus (mosquito) and vero (african green monkey kidney) cell cultures. these organisms could not be isolated by injection of the infected ticks or blood into embryonated chicken eggs, guinea pigs, or voles (microtus pennsylvanicus), but fluid cultures of grace' ...	1975	241251
transovarial transmission of rickettsia-like microorganisms in mosquitoes.	the wolbachiae found in culex pipiens and the tafahi strain of the a. scutellaris group are small rickettsia-like symbionts of the gonads. they are extrachromosomal self-replicating units that are vertically transmitted through the ovaries. their presence in the only two groups of mosquitoes known to exhibit incompatibility, the fact that they are found in only the tafahi strain, and the loss of incompatibility after removal of wolbachia in c. pipiens are compelling evidence for the role that wo ...	1975	20018