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1.
This study determined the effects of nitrite on different life stages of the Amazon river prawn Macrobrachium amazonicum. Prawns of each life stage (postlarvae, juveniles and adults) were stocked in 24 experimental units (n?=?10 prawns), under a complete randomized design. Individuals were exposed to nitrite (0, 1, 2, 4, 8 and 16 mg L?1). The median lethal concentration after 96 h (96 h LC50) was calculated through the Weibull I. The mortality results showed that M. amazonicum is slightly less tolerant to nitrite than other species of Macrobrachium. The 96 h LC50 for postlarvae, juveniles and adults of M. amazonicum were of 1.49, 2.36 and 2.34 mg nitrite/L, respectively. Nitrite intoxication risk quotient suggest moderated risk to low risk to the species. Usually in production systems nitrite values are lower than safe levels suggested in this study (0.1 mg L?1 to postlarvae and 0.2 mg L?1 nitrite to juvenile and adults), which makes our results appropriate for the production of this species.  相似文献   

2.
《Ticks and Tick》2023,14(4):102182
Ticks are vectors for several pathogens, including bacteria belonging to the Rickettsia genus, such as Rickettsia rickettsii and Rickettsia parkeri, the causative agents of spotted fever. The aim of the present study was to investigate the tick species richness and rickettsial agents associated with wild birds captured in the Humaita Forest Reserve, Acre, in the Western Amazon region. Wild birds were captured with ornithological nets for visual inspection with the purpose of collecting ticks, which were identified through morphological analyses and molecular tests for several genes (12S rDNA, 16S rDNA, gltA, ompA, and sca4). A total of 607 wild birds were captured, 12% of which were parasitized by 268 ticks of the Amblyomma genus, with new host-parasite associations reported for Amblyomma calcaratum, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, and Amblyomma varium. Of the total ticks collected, 113 were tested for the presence of rickettsial DNA fragments, with 19 testing positive for R. parkeri in A. geayi, Rickettsia tamurae-like in Amblyomma sp., and Rickettsia amblyommatis in A. geayi, A. longirostre, and Amblyomma sp. We detected R. tamurae-like in Amblyomma larvae for the first time in the Western Brazilian Amazon biome, and registered spotted fever group rickettsiae, although the relevance of the detected species in a public health context should be further explored in South America, as well as new host-parasite interactions in this underexplored region.  相似文献   

3.
《Ticks and Tick》2023,14(6):102234
The present study aimed to identify tick and flea species infesting captive tapirs (Tapirus terrestris and Tapirus kabomani) in the Brazilian Amazon. Ectoparasites were collected from tapirs chemically restrained in Zoo-botanical Parks, breeding facilities, conservationists and, environmental compensation areas in the states of Amapá, Amazonas, and Pará. After collection, the tick and flea specimens were placed in plastic pots containing isopropanol and identified according to dichotomous keys. Ectoparasite infestations were observed in 55% (18/33) tapirs, of which 61% (11/18) were single infestations with ticks or fleas, and 39% (7/18) were mixed infestations with different species of ticks and/or fleas. In total, 227 ticks (15 larvae, 107 nymphs, 38 females and 67 males) and 14 fleas (eight females and six males) were collected, identifying four tick species (Amblyomma cajennense sensu stricto , Amblyomma naponense, Amblyomma oblongoguttatum, and Amblyomma pacae) and three flea species and/or subspecies (Ctenocephalides felis felis, Rhopalopsyllus australis australis, and Tunga penetrans). In conclusion, infestations with Ixodidae ticks and Rhopalopsyllidae, Pulicidae and Tungidae fleas were found in captive tapirs in the Brazilian Amazon, and A. cajennense s.s. was the most frequent species. Additionally, the present study reports new associations between A. pacae and R. a. australis with T. terrestris and between A. cajennense s.s. with T. kabomani.  相似文献   

4.
This study aimed to evaluate the concentrations of toxic elements (As, Cd, Hg, Pb) and essential trace elements (Co, Cu, Cr, Fe, Mn, Mo, Ni, Se, Zn) in the freshwater shrimp M. amazonicum in the region of Santarem (lower Amazonia), which is affected by mining activities. The level of metal accumulation in the shrimp was found to be similar to that measured in other regions affected by anthropogenic polluted in both in Brazil and elsewhere, and does not pose a significant risk for human consumption. The different patterns of metal accumulation between the Amazon and Tapajos basins appear to be (at least partly) related to respectively bauxite exploitation and gold mining in the region. Bioaccumulation of the trace elements Co, Fe, and Mn mainly occurred in the visceral part of the shrimps from the Amazon river.  相似文献   

5.
The densities of microfilariae of Mansonella ozzardi in different regions of the body of infected individuals were studied. The density in venous blood closely approximated to that found in finger capillaries, but was significantly lower than the densities in capillaries of the scapular region and buttocks. A possible explanation for this concentration of microfilariae is the lack of glomi in these two sites, which consequently have a lower flow of blood than areas where glomi occur and where microfilarial densities are lower. No relationship was found between blood and skin densities in the buttocks and scapular region, probably due to the inadequacy of the skin snip method used for the detection of this species of filaria. It was concluded that the most acceptable detection method for M. ozzardi remains the sampling of finger capillary blood. It could not be decided, due to the paucity of data, whether any relationship exists between skin microfilarial densities and the biting sites of the vectors.  相似文献   

6.
《Ticks and Tick》2020,11(3):101385
A new argasid (Argasidae) tick is herein described based on morphology and molecular data obtained from larvae parasitizing Octodon degus and from ticks collected inside burrows in northern Chile. Unfed laboratory-reared larvae were mounted in slides for morphometrical and morphological analyses. Larvae of Ornithodoros octodontus n. sp. share morphological traits with Ornithodoros quilinensis and Ornithodoros xerophylus, two species associated with rodents in the Argentinean Chaco. However, a longer hypostome with two rows of 21 and 22 denticles each one, and conspicuous leaf-shaped anal plates separate O. octodontus. While nymphal stages of O. octodontus lack cheeks and possess a micromammillated dorsal integument, adults have cheeks and exhibit markedly irregular mammillae along their dorsal surface. Phylogenetic analyses of neotropical Argasidae based on mitochondrial 16S rDNA sequences point that O. octodontus forms a monophyletic group with O. xerophylus and an unidentified Ornithodoros sp. from Bolivia, all of them associated with burrow-dweller rodents. Ornithodoros aragaoi and Ornithodoros davisi, two rare species collected once only in the Peruvian Andean Plateau during 1955 are morphologically closely related with adults and nymphs of O. octodontus. Biological observations of O. octodontus revealed autogenic females. For the moment, subgeneric classification of this new species depends on further biological studies. The fauna of ticks occurring in Chile is now represented by 22 species, 11 belonging to the Argasidae family.  相似文献   

7.
《Ticks and Tick》2023,14(6):102239
In 2020, adult hard ticks (males and females) were collected from great horned owls [Bubo virginianus (Gmelin, 1788)] in the coastal region in southern Brazil. The engorged females were allowed to oviposit in the laboratory and hatched larvae could be obtained. Analyses of the external morphology of the adult ticks revealed that they represent a new species, which was named Amblyomma monteiroae n. sp. Partial sequences of the mitochondrial 16S rRNA gene and the nuclear second internal transcribed spacer (ITS2) were generated from a male and a female. Their 16S rRNA haplotypes were identical to each other and closest (96% identity) to corresponding sequences of Amblyomma parvitarsum Neumann, 1901, and 90% identical to Amblyomma neumanni Ribaga, 1902. Their ITS2 haplotypes were 95.8 to 96.0 identical to the single ITS-2 partial sequence of A. parvitarsum available in GenBank. In the phylogenetic trees inferred by both 16S rRNA and ITS2 partial sequences, A. monteiroae n. sp. formed a clade with A. parvitarsum, with A. neumanni branching sister to this clade. Amblyomma monteiroae n. sp. is genetically and morphologically related to A. parvitarsum. Both tick species are unique in combining the following morphological characters: scutum extensively ornate; eyes rounded and bulging; coxa I with two moderate pointed spurs, the external longer than the internal; a single triangular short spur on coxae II-III; presence of two spines on the tibia of legs II-IV; hypostomal dentition 3/3, trochanters without spurs. However, the males of the two species can be separated by specific features in palps and festoons, whereas the females differ in specific features of the coxal spurs. The larva of A. monteiroae n. sp. can be morphologically distinguished from A. parvitarsum only by morphometry, with the former species being slightly smaller. Currently, A. monteiroae n. sp. is restricted to southern Brazil, and the only known host is B. virginianus (Strigiformes: Strigidae). The present study increases the Amblyomma Brazilian fauna to 34 species.  相似文献   

8.
Laboratory techniques are described for evaluating the lethal and behavioral impact of pesticides on a range of stream macroinvertebrates under continuous through-flow and simulated stream conditions. The same basic test unit has been used, with slight modifications, to study the reactions of bothSimulium larvae and non-target stream invertebrates. On the basis of a standard 1-hr exposure period to different concentrations followed by a 24-hr holding period in a continuous flow of clean water, different test organisms showed wide and consistent differences in tolerance to each of the two insecticides tested. The widest difference between two organisms occurred in the case of the Amphipod,Gammarus pulex (LC90-95, >> 1 ppm) which was found to be about 5000 x more tolerant to temephos than are nymphs of the mayfly,Baetis rhodani. (LC 90–95, 0.001– 0.002 ppm) The widest difference in the reactions of any one species is shown on the part ofGammarus which is about 100 times more susceptible to chlorpyrifos (LC 90–95, 0.05–0.1 ppm) than to temephos. The susceptibility levels of other indicator species such asAgrion,Hydropsyche, Brachycentras, Ephemera, etc. are discussed in relation to susceptibility levels ofSimulium larvae under the same test conditions, and also in relation to current field dosages of the two insecticides in practical and experimentalSimulium control.  相似文献   

9.
The Amazon region has recently been considered as endemic in Latin America. In Bolivia, the vast Amazon region is undergoing considerable human migrations and substantial anthropization of the environment, potentially renewing the danger of establishing the transmission of Chagas disease. The cases of human oral contamination occurring in 2010 in the town of Guayaramerín provided reasons to intensify research. As a result, the goal of this study was to characterize the species of sylvatic triatomines circulating in the surroundings of Yucumo (Beni, Bolivia), a small Amazonian city at the foot of the Andes between the capital (La Paz) and Trinidad the largest city of Beni. The triatomine captures were performed with mice-baited adhesive traps mostly settled in palm trees in forest fragments and pastures. Species were identified by morphological observation, dissection of genitalia, and sequencing of three mitochondrial gene fragments and one nuclear fragment. Molecular analysis was based on (i) the identity score of the haplotypes with GenBank sequences through the BLAST algorithm and (ii) construction of phylogenetic trees. Thirty-four triatomines, all belonging to the Rhodnius genus, of which two were adult males, were captured in palm trees in forest fragments and pastures (overall infestation rate, 12.3%). The morphology of the phallic structures in the two males confirmed the R. stali species. For the other specimens, after molecular sequencing, only one specimen was identified with confidence as belonging to Rhodnius robustus, the others belonged to one of the species of the Rhodnius pictipes complex, probably Rhodnius stali. The two species, R. robustus and R. stali, had previously been reported in the Alto Beni region (edge of the Amazon region), but not yet in the Beni department situated in the Amazon region. Furthermore, the difficulties of molecular characterization of closely related species within the three complexes of the genus Rhodnius are highlighted and discussed.  相似文献   

10.
《Ticks and Tick》2020,11(6):101546
The aim of this work was to evaluate the presence of Borrelia infection in Ixodes sp. cf. Ixodes affinis ticks from Argentina. Specimens of Ixodes sp. cf. I. affinis were collected on vegetation and birds in five locations belonging the most humid part of the Chaco Biogeographic Province. Specimens were tested for Borrelia infection by nested-PCR targeting the flaB gene and the rrfA-rrlB intergenic spacer region (IGS), sequenced and phylogenetically analyzed. A total of 48 Ixodes sp. cf. I. affinis (12 questing adults from vegetation and 20 nymphs and 16 larvae on nine bird species: Arremon flavirostris, Basileuterus culicivorus, Campylorhamphus trochilirostris, Myiothlypis leucoblephara, Tachyphonus rufus, Thlypopsis sordida, Turdus amaurochalinus, Turdus rufiventris and Troglodytes aedon) were collected. Twelve adults, 14 nymphs and 11 larvae (3 individually and 8 in 3 pools) were analyzed. Partial sequences were detected in 6 adults, 11 nymphs and 4 larvae (2 individual and 2 pools). Phylogenetically, the Borrelia found in Ixodes sp. cf. I. affinis belongs to the B. burgdorferi sensu lato (s. l.) complex. The partial sequences obtained from the borrelian gene flaB and IGS were associated to two groups formed by sequences previously detected in Ixodes fuscipes, Ixodes longiscutatus and Ixodes pararicinus from the Southern Cone of America in northern Argentina, southern Brazil and Uruguay. The results of this work suggest that the haplotypes of B. burgdorferi s. l. complex detected in the three species of the I. ricinus complex distributed in the Southern Cone of America are related and widely distributed.  相似文献   

11.
In the present work, we carried out a morphological, biometrical and molecular study of whipworms Trichuris Roederer, 1761 (Nematoda: Trichuridae) parasitizing Papio ursinus Keer 1792 (Chacma baboon). Biometrical and molecular data suggest a new species of Trichuris parasitizing baboons. In addition of main morphological features (spicule, spicule sheath, spicule tube, proximal cloacal tube, distal cloacal tube, vulva, vagina), the mean values of individual variables between Trichuris colobae, Trichuris suis, Trichuris trichiura examined by Student's t tests suggest that T. ursinus n. sp. constitutes a new species. The combined analysis of three markers (cox1, cob and ITS2) revealed a sister relationships between T. colobae and T. ursinus n. sp. Mitochondrial sequences revealed a higher inter-specific similarity between T. ursinus n. sp., T. suis and T. colobae. Phylogenetic hypotheses for both mitochondrial genes strongly supported distinct genetic lineages corresponding to different species of the genus Trichuris associated with certain hosts. Thus, T. suis, T. colobae and T. ursinus n. sp. appeared as a sister group and separated from Trichuris spp. from humans and other species of primates.  相似文献   

12.
《Ticks and Tick》2020,11(3):101373
This Turkey-based study investigated the presence of various tick-borne microorganisms in a broad-range of host-seeking ticks (n = 1019) that exhibit both hunter and ambusher characteristics. All collected ticks were analyzed individually via PCR-sequencing, resulting in the identification of 18 different microorganisms: six Babesia spp., including one putative novel species (Ba. occultans, Ba. crassa, Ba. rossi, Babesia sp. tavsan1, Babesia sp. tavsan2, and Babesia sp. nov.); six SFG rickettsiae (Ri. aeschlimannii, Ri. s. mongolitimonae, Ri. slovaca, Ri. raoultii, Ri. monacensis, and Ri. hoogstraalii); two Borrelia burgdorferi sensu lato spp. (Bo. afzelii and Bo. lusitaniae); two unnamed Hepatozoon spp.; Theileria annulata; and Hemolivia mauritanica. This provided evidence for the natural transstadial survival of these tick-borne microorganisms in adult ticks (in addition a nymph) of Turkey. Surprisingly, this study determined the presence of five different microorganisms (Ba. crassa, Ba. rossi, Babesia sp. Ucbas, Hepatozoon sp., and Ri. hoogstraalii) in host-seeking Haemaphysalis parva adults, for which poor data exist on its vectorial competence. Therefore, this study provides important data indicating the potential vectorial capacity of Ha. parva. This study also revealed the presence of the close ecological and evolutionary relationships between two important vector ticks, Hyalomma marginatum and Hy. aegyptium and determined genetic variations (distinct phylogenetic divergences inside the main clades) in some pathogenic SFG rickettsiae that are found in these ticks. Additionally, the presence of two Babesia species described very recently in hares with unknown vectors, namely Babesia sp. tavsan1 and Babesia sp. tavsan2, were detected for the first time in ticks. Finally, two unnamed Hepatozoon spp. were detected in Haemaphysalis ticks and their phylogenetic positions were demonstrated. Consequently, this study provides important data on the diversity of tick-borne microorganisms in host-seeking ticks and on potentially novel microorganisms (Babesia and Hepatozoon species) and their possible vectors (Ha. parva, Ha. sulcata, Hy. aegyptium, Hy. marginatum, and Rh. turanicus).  相似文献   

13.
The subgenus Transphlebotomus comprises sand fly species with distribution markedly restricted to the Mediterranean basin and suspected of Leishmania transmission. Only three species, Phlebotomus mascittii, Phlebotomus canaaniticus and Phlebotomus economidesi, have been described up to the present. Due to their similar morphology, proper identification remains difficult and relies mainly on molecular markers. We studied sand fly species of this subgenus from Crete and south-western coast of Anatolia. Based on the sequencing analysis of mitochondrial genes (cytochrome b, NADH dehydrogenase subunit 4, cytochrome oxidase I), two new Transphlebotomus species were identified and subsequently distinguished also by morphological characters: Phlebotomus anatolicus n. sp. and Phlebotomus killicki n. sp. Moreover, Ph. economidesi, previously only recorded from Cyprus, was found in Turkey sympatrically with these two new species. Based on the divergence time estimates, the first split has occurred in the subgenus Transphlebotomus ∼10 million years ago and the paleogeographic events took place around the Aegean and Mediterranean regions were suggested as the main drivers of the diversification of the subgenus. Our findings indicate that for Transphlebotomus species, morphological identification should be confirmed by molecular approaches, especially for investigations concerning their possible vectorial role in Leishmania transmission.  相似文献   

14.
In this study, a total of 319 ticks were obtained from hedgehogs (Erinaceus concolor). All ticks were pooled into groups and screened by PCR for tick-borne pathogens (TBPs). PCR and sequence analyses identified the presence of a novel Babesia sp. in adult Haemaphysalis erinacei. In addition, the presence of natural transovarial transmission of this novel Babesia sp. was detected in Ha. erinacei. According to the 18S rRNA (nearly complete) and partial rRNA locus (ITS-1/5.8S/ITS-2) phylogeny, it was determined that this new species is located within the Babesia sensu stricto clade and is closely related to Babesia spp. found in carnivores. Furthermore, the presence of three pathogenic spotted fever group (SFG) rickettsiae was determined in 65.8% of the tick pools: Rickettsia sibirica subsp. mongolitimonae in Hyalomma aegyptium (adult), Hyalomma spp. (larvae), Rhipicephalus turanicus (adult), and Ha. erinacei (adult); Rickettsia aeschlimannii in H. aegyptium (adult); Rickettsia slovaca in Hyalomma spp. (larvae and nymphs) and H. aegyptium (adult). To our knowledge, this is the first report of R. sibirica mongolitimonae in H. aegyptium, Ha. erinacei, and Rh. turanicus, and the first report of R. slovaca in H. aegyptium. In addition, the presence of a single Hemolivia mauritanica haplotype was detected in H. aegyptium adults. Consequently, the presence of a novel Babesia sp. has been identified in a new candidate vector tick species in this study. Additionally, three SFG rickettsiae that cause infections in humans were identified in ticks collected from hedgehogs. Therefore, environmental wildlife monitoring for hedgehogs should be carried out for ticks and tick-borne pathogens in the region. Additionally, studies regarding the reservoir status of hedgehogs for the aforementioned pathogens must be carried out.  相似文献   

15.
Understanding waterborne protozoan parasites (WPPs) diversity has important implications in public health. In this study, we evaluated a NGS-based method as a detection approach to identify simultaneously most important WPPs using 18S rRNA high-throughput sequencing. A set of primers to target the V4 18S rRNA region of WPPs such as Cryptosporidium spp., Giardia sp., Blastocystis sp., Entamoeba spp, Toxoplasma sp. and free-living amoebae (FLA) was designed. In order to optimize PCR conditions before sequencing, both a mock community with a defined composition of representative WPPs and a real water sample inoculated with specific WPPs DNA were prepared. Using the method proposed in this study, we have detected the presence of Giardia intestinalis, Acanthamoeba castellanii, Toxoplasma gondii, Entamoeba histolytica and Blastocystis sp. at species level in real irrigation water samples. Our results showed that untreated surface irrigation water in open fields can provide an important source of WPPs. Therefore, the methodology proposed in this study can establish a basis for an accurate and effective diagnostic of WPPs to provide a better understanding of the risk associated to irrigation water.  相似文献   

16.
The genus Anopheles includes mosquito vectors of human malaria and arboviruses. In sub-Saharan Africa, the anopheline fauna is rich of nearly 150 species, few of which are anthropophilic and capable of transmitting pathogens to humans. Some of the remaining species are found in forests far from human environments and are vectors of wildlife pathogens. The diversity and the biology of these species have yet to be fully described. As a contribution to furthering knowledge of sylvan Anophelinae, using morphological and molecular tools we describe a new Anopheles species collected in Gabon (Central Africa), which we have named Anopheles gabonensis n. sp. We also molecularly screened this species to detect infections by Plasmodium parasites. The results showed the species to have been infected by Plasmodium vinckei, a rodent parasite. We discuss the role of An. gabonensis n. sp. in the transmission of P. vinckei in the rainforest areas of Central Africa and its potential to transfer pathogens to humans.  相似文献   

17.
The aim of this study was to clarify the taxonomic status of named species within the genus Mycobacterium. The analysis of genomes belonging to 174 taxa (species or subspecies) of the genus Mycobacterium was conducted using both the Average Nucleotide Identity and the Genome to Genome Distance. A number of synonymous taxa were detected. The list of synonyms includes: two subspecies of M. chelonae (M. chelonae subsp. bovis and M. chelonae subsp. gwanakae), two subspecies of M. fortuitum (M. fortuitum subsp. fortuitum and M. fortuitum subsp. acetamidolyticum), four subspecies of M. avium (M. avium subsp. avium, M. avium subsp. silvaticum, M. avium subsp. paratuberculosis and “M. avium subsp. hominissuis”), two couples of subspecies of M. intracellulare (M. intracellulare subsp. intracellulare/M. intracellulare subsp. paraintracellulare and M. intracellulare subsp. chimaera/M. intracellulare subsp. yongonense), the species M. austroafricanum and M. vanbaalenii, the species M. senegalense and M. conceptionense, the species M. talmoniae and M. eburneum and the species M. marinum, M. ulcerans and M. pseudoshottsii. Furthermore one species were reclassified as subspecies of another mycobacterium: M. lepraemurium was reclassified as a subspecies of M. avium (M. avium subsp. lepraemurium). The updates to nomenclature are proposed basing on the priority of names according the Code of nomenclature of prokaryotes. For two species (M. bouchedurhonense and M. marseillense) the loss of standing in nomenclature is proposed because of unavailability of respective type strains in culture collections.  相似文献   

18.

Background

The aim of this paper was to study the prevalence and intensity of Anisakids larvae in the long tail tuna fish captured from Iranian shores of Persian Gulf.

Methods

Different organs including skin, abdominal cavity, stomach and intestinal contents, stomach sub serous tissues, liver, spleen, gonads and 20 grams of muscles of 100 long tail tuna fish (Thannus tonggol) caught from waters of the north parts of Persian Gulf were searched for anisakid nematodes larvae. Twenty grams of around the body cavity muscles were digested in artificial gastric juice. Different organs and digested muscles were examined with naked eyes for the presence of anisakids larvae. The collected larvae were preserved in 70% alcohol containing 5% glycerin, and cleared in lactophenol for identification.

Results

Our findings revealed that 89% of fish harbored 3rd stage larvae of Anisakis sp. of which 2% were infected with both Anisakis and Raphidascaris. All inspected organs except that of skin were found to be infected, while stomach sub serous tissues were the most infected organ (80%) followed by abdominal cavity (10%), liver (4%), testicle (3%), stomach contents and spleen (2%) and intestinal contents (1%). Intestine and abdominal cavity were the organs harbored Raphidascaris sp. Digested muscles were free of parasite. Mean intensity was low for both species and ranged between 1.5 for Raphidascaris sp. and 3.67 for Anisaki sp.

Conclusion

Anisakids larvae especially Anisakis are very prevalent in some fish including tunas of Persian Gulf, and consumption of infected fish if it is not properly cooked may lead to human anisakiasis.  相似文献   

19.
BackgroundPhylogenetic studies of bacteria have been based so far either on a single gene (usually the 16S rRNA) or on concatenated housekeeping genes. For what concerns the genus Mycobacterium these approaches support the separation of rapidly and slowly growing species and the clustering of most species in well-defined phylogenetic groups. The advent of high-throughput shotgun sequencing leads us to revise conventional taxonomy of mycobacteria on the light of genomic data. For this purpose we investigated 88 newly sequenced species in addition to 60 retrieved from GenBank and used the Average Nucleotide Identity pairwise scores to reconstruct phylogenetic relationships within this genus.ResultsOur analysis confirmed the separation of slow and rapid growers and the intermediate position occupied by the M. terrae complex. Among the rapid growers, the species of the M. chelonae-abscessus complex belonged to the most ancestral cluster. Other major clades of rapid growers included the species related to M. fortuitum and M. smegmatis and a large grouping containing mostly environmental species rarely isolated from humans. The members of the M. terrae complex appeared as the most ancestral slow growers. Among slow growers two deep branches led to the clusters of species related to M. celatum and M. xenopi and to a large group harboring most of the species more frequently responsible of disease in humans, including the major pathogenic mycobacteria (M. tuberculosis, M. leprae, M. ulcerans). The species previously grouped in the M. simiae complex were allocated in a number of sub-clades; of them, only the one including the species M. simiae identified the real members of this complex. The other clades included also species previously not considered related to M. simiae. The ANI analysis, in most cases supported by Genome to Genome Distance and by Genomic Signature-Delta Difference, showed that a number of species with standing in literature were indeed synonymous.ConclusionsGenomic data revealed to be much more informative in comparison with phenotype. We believe that the genomic revolution enabled by high-throughput shotgun sequencing should now be considered in order to revise the conservative approaches still informing taxonomic sciences.  相似文献   

20.
Entomopathogenic fungi attack Chagas disease vectors, and there is a need of effective isolates for development of biological control. Ten isolates of Metarhizium spp., four of Isaria cateniannulata and two of an Isaria sp., all isolated with Triatoma infestans as a bait insect from soils collected in Central Brazil, and tested under laboratory conditions were effective against third instar nymphs of T. infestans. This is the first report of pathogenicity of M. flavoviride var. pemphigi, M. robertsii and I. cateniannulata against T. infestans. M. robertsii IP 34 and I. cateniannulata IP 141 are among the most virulent fungi reported, and both have potential for integrated control of triatomine vectors.  相似文献   

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