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1.
Bacterial and archaeal community structures and diversity of three different sedimentary environments (BH1A, BH2A and BH3A) in the acid pit lake of a chalcopyrite mine at Touro (Spain) were determined by 16S rRNA gene PCR-DGGE and sequencing of clone libraries. DGGE of bacterial and archaeal amplicons showed that the sediments harbor different communities. Bacterial 16S rRNA gene sequences were assigned to Acidobacteria, Actinobacteria, Cyanobacteria, Planctomycetes, Proteobacteria, Chloroflexi and uncultured bacteria, after clustering into 42 operational taxonomic units (OTUs). OTU 2 represented approximately 37, 42 and 37 % of all sequences from sediments BH1A, BH2A and BH3A, respectively, and was phylogenetically related to uncultured Chloroflexi. Remaining OTUs were phylogenetically related to heterotrophic bacteria, including representatives of Ferrithrix and Acidobacterium genera. Archaeal 16S rRNA gene sequences were clustered into 54 OTUs. Most of the sequences from the BH1A sediment were assigned to Euryarchaeota, whereas those from BH2A sediment were assigned to Crenarchaeota. The majority of the sequences from BH3A sediment were assigned to unclassified Archaea, and showed similarities to uncultured and unclassified environmental clones. No sequences related to Acidithiobacillus and Leptospirillum, commonly associated with acid mine drainage, were detected in this study.  相似文献   

2.
Ticks and tick-borne diseases are important in human and livestock health worldwide. In November 2012, ixodid ticks were collected and identified morphologically from cattle and wild animals in the Maswa district and Iringa urban, Tanzania. Amblyomma gemma, A. lepidum, and A. variegatum were identified from Maswa cattle, and A. variegatum was the predominant species. A. marmoreum, Hyalomma impeltatum, and Rhipicephalus pulchellus were identified from Iringa cattle in addition to the above 3 Amblyomma species, and A. gemma was the most abundant species. Total 4 Amblyomma and 6 Rhipicephalus species were identified from wild animals of the 2 areas. A. lepidum was predominant in Maswa buffaloes, whereas A. gemma was predominant in Iringa buffaloes. Overall, A. variegatum in cattle was predominant in the Maswa district and A. gemma was predominant in Iringa, Tanzania.  相似文献   

3.
The aims of this work were: (i) to determine the distribution and abundance of Agriotes lineatus, (ii) correlate the abundance with the prevailing climatic conditions to establish how temperature and rainfall are influencing the dominance, and (iii) to determine the activity characteristics of the adults. Investigations were conducted in 17 fields grouped in four regions characterized by different climatic conditions. Using sex pheromone traps the most important Agriotes species (A. lineatus L., A. sputator L., A. obscurus L., A. brevis Cand. and A. ustulatus Schall.) were collected. The monitoring period for A. brevis, A. sputator, A. lineatus and A. obscurus was from the 18th to the 32nd, and for A. ustulatus from the 23rd to the 32nd week of the year. A total of 61,247 individuals Agriotes were captured, of which 24,916 individuals were A. lineatus. Abundance and dominance of A. lineatus were significantly higher in the region of Zagreb compared to other regions. Moving east, rainfall decreased and temperatures increased and associated with that the abundance and dominance indices were lower. It was determined that the abundance of A. lineatus was negatively correlated with average air temperature (r?=??0.5201; p?<?0.0001). Compared to earlier data from the region of Zagreb the dominance index decreased. This might be a result of climate change as established average yearly temperature in these regions increased for 1.04 °C compared to the average data for the period 1961–1990. Other potentially damaging Agriotes species (A. brevis and A. ustulatus) were also present in high abundances in some micro-regions.  相似文献   

4.
Qualitative and quantitative differences in population growth patterns of Aphelenchoides rutgersi from Florida, A. sacchari from Jamaica, A. dactylocercus from Great Britain, and A. cibolensis from New Mexico were assessed on 28 species of fungi. The patterns of population growth of A. rutgersi and A. sacchari were statistically similar although not identical, and they differed considerably from those of A. dactylocercus and A. cibolensis. It is suggested that A. rutgersi and A. sacchari, from Florida and Jamaica respectively, may be more closely related to each other than to either A. dactylocercus or A. cibolensis.  相似文献   

5.
6.
Fifteen Frankia strains from five different plant species were analyzed by two-dimensional polyacryl-amide gel electrophoresis to determine their relatedness by comparing the polypeptide patterns obtained. Three major subgroups (A, C, and D) were found in the Alnus-Comptonia-Myrica cross-inoculation group. An isolate from Purshia tridentata had a unique protein pattern and represents a distinct group of frankiae. Members of group A were isolated from root nodules of Alnus incana subsp. rugosa and Alnus viridis subsp. crispa. Group C organisms were from A. incana subsp. rugosa and Comptonia peregrina nodules, and group D organisms were from A. incana subsp. rugosa, A. viridis subsp. cripsa, and Myrica pensylvanica root nodules. Isolates from each gel group were obtained at several widely separated geographical locations. The results indicate that two-dimensional polyacrylamide gel electrophoresis is useful for identifying Frankia isolates.  相似文献   

7.
Fraxin and esculin were characterized in stems and fruits of A. deliciosa (kiwifruit) and A. chinensis. These two coumarins were not present in several other Actinidia species belonging to the four sections of the genus Actinidia such as A. callosa, A. eriantha, A. hemsleyana, A. arguta, A. kolomikta, A. melanandra, A. polygama. Our results support the opinion that A. deliciosa and A. chinensis are closely related and likely belonging to the same species.  相似文献   

8.
Oviposition behavior and offspring fitness of the parasitoid Aphidius gifuensis (Ashmead) were compared on three aphid species, Sitobion avenae F., Myzus persicae (Sulzer), and Aphis gossypii Glover using wasps collected from both S. avenae and M. persicae. A. gifuensis produced more mummies and adults on S. avenae and M. persicae than on A. gossypii regardless of the host of origin. Mummy production was influenced by attack rate and percentage of aphids superparasitized. The F1 generations from S. avenae and M. persicae were more female-biased and wasps were larger than those from A. gossypii. Although there were significant differences in development time of A. gifuensis in the three aphid species, the difference was generally shorter than one day. Fewer mummies were produced when A. gifuensis was transferred between S. avenae and M. persicae, but no significant difference was observed in emergence rate, percentage of female offspring, or body size. The effects of host species on A. gifuensis female performance and offspring fitness are discussed, along with the potential for using A. gifuensis to control M. persicae and A. gossypii.  相似文献   

9.
A slightly modified Giemsa smear procedure consistently demonstrated Wolbachia pipientis in Culex pipiens and the Wolbachia species of infected members of the Aedes scutellaris group. Aposymbiosis was induced in Aedes polynesiensis by treatment with 0.017 mg/ml tetracycline hydrochloride or by rearing larvae at temperatures of 32–33°C for 5–7 days. Aposymbiotic females were incompatible with infected males but the reciprocal cross was fertile. By light and electron microscopy wolbachiae were found in ovaries of Aedes albopictus, A. cooki, A. Niuafo'ou sp., A. polynesiensis from American Samoa and Tahiti, A. riversi, A. Tafahi sp., and A. upolensis. Wolbachiae were not detected in A. alcasidi, A. oceanicus, A. triseriatus, Culex peus, two laboratory colonies of C. pipiens, Culiseta incidens, Toxorhynchites amboinensis, or T. brevipalpis. Wolbachiae were found also in the ovarian follicular epithelium of A. albopictus. This is the first record of mosquito wolbachiae in nongerminal gonadal tissue.  相似文献   

10.
Solute-carrier family 27A molecules are integral transmembrane proteins that play a fundamental role in the uptake of long-chain fatty acids into mammalian cells. Our goal was to characterize this multigene family in pigs. Chromosomal location of the six porcine SLC27A genes was determined by radiation hybrid mapping and indicated that the six genes map to six different chromosomal locations. Moreover, we analyzed SLC27A mRNA expression in six pig tissues by quantitative RT-PCR. While SLC27A1, SLC27A3 and SLC27A4 were expressed in most, if not all, analyzed tissues, SLC27A2, SLC27A5 and SLC27A6 were predominantly expressed in the liver. In general, pig and human SLC27A mRNA expression profiles were remarkably concordant, although important differences were observed for SLC27A1 and SLC27A6 mRNAs. Discrepancies between mRNA expression profiles have been observed even in closely related primate species, and they might reflect the acquisition of regulatory changes promoting evolutionary adaptation.  相似文献   

11.
Anaplasmosis poses a great threat to the livestock industry and human health in most tropical and subtropical regions of the world. This study investigated the presence of Anaplasma in sheep from Heilongjiang Province, northeastern China. A total of 341 blood samples were detected by PCR with species-specific primers based on the msp4 gene of Anaplasma ovis, 16S rRNA gene of Anaplasma phagocytophilum and Anaplasma bovis and gltA gene of Anaplasma capra. The results showed that Anaplasma infection was found in 103 (30.2%) of 341 sheep. The infection rates were 2.6%, 8.8%, 15.8% and 10.0% for A. ovis, A. phagocytophilum, A. bovis and A. capra in sheep, respectively. Co-infection involving two Anaplasma species was found in 25 sheep (8.0%), which were usually A. phagocytophilum and A. bovis (72.0%). Co-infection involving A. phagocytophilum, A. capra, A. ovis with zoonotic potential, was found in one sheep. Sequence analysis revealed that the isolates of A. ovis, A. bovis and A. phagocytophilum identified in sheep were closely related to those previously reported in ticks and other animal hosts. Phylogenetic analysis showed that A. capra could be classified into two distinct clusters based on the gltA gene and the isolates identified in sheep from this study were clustered in the A. capra genotype II, which was clearly distinct with the human isolates. The findings in this study report four Anaplasma species and a novel A. capra genotype in sheep from northeastern China, and improve our knowledge of Anaplasma, contributing to the control of ovine anaplasmosis.  相似文献   

12.
Susceptibility to five antimicrobials was determined for Bacteroides spp. (n = 52) and Parabacteroides distasonis (n = 8). All isolates were susceptible to metronidazole. The resistance rates to ampicillin, cefoxitin, tetracycline and clindamycin were 98%, 9.6%, 65.3% and 19.2% of the Bacteroides strains, respectively. The genes cepA, cfiA, cfxA, tetQ, ermF and nim were found in 69.2%, 17.3% 9.6%, 50%, 7.7% and 3.8% for these strains respectively. All P. distasonis strains were resistant to ampicilin. Cefoxitin, tetracycline and clindamycin resistance rates were 75%, 87.5% and 50%, respectively. The ermF and nim genes were absent and 37.5%, 12.5%, 12.5% and 87.5% of this strains possessed cepA, cfiA, cfxA and tetQ genes, respectively. Ten cfiA gene positive strains of Bacteroides and Parabacteroides were submitted to E-test with imipenem and amoxicillin–clavulanate. The resistance rate to imipenem was 4.1% and 8.3% to amoxicillin–clavulanate. This feature is for the first time described in Brazil.  相似文献   

13.
《Genomics》2020,112(6):3893-3902
This study presented 96 cox1 and 76 cox3 genes of Amphioctopus neglectus populations. Three distinct lineages were formed from phylogenetic trees and networks constructed using haplotypes. Mitogenomes of A. neglectus-a and A. neglectus-b as the representatives of two lineages separated from population genetics were sequenced to compare with A. neglectus at the genome-level. Amphioctopus neglectus-a showed significant differences with A. neglectus, mainly reflected in gene length, intergenic regions and the secondary structure of tandem repeat motifs. Notably, two sequence deletions in mitogenomes of the two representative species were detected in different positions of major non-coding regions, which were the most distinct differences with A. neglectus. Pairwise genetic distances and the phylogenetic analysis supported the relationship of (A. neglectus-a + (A. neglectus + A. neglectus-b)). This study suggested that A. neglectus-a should be considered as a potential cryptic species of this complex, while A. neglectus-b needed further verification to be defined.  相似文献   

14.
Sixty-three nalidixic acid-resistant Aeromonas sp. isolates were obtained from imported shrimp. Phylogenetic analysis of gyrB sequences indicated that 18 were A. enteropelogenes, 26 were A. caviae, and 19 were A. sobria. Double missense mutations in the quinolone resistance-determining region (QRDR) of gyrA at codon 83 (Ser→Val/Ile) and codon 92 (Leu→Met) coupled with a point mutation of parC at codon 80 (Ser→Ile/Phe) conferred high levels of quinolone resistance in the isolates. A majority of A. enteropelogenes and A. caviae strains harbored toxin genes, whereas only a few A. sobria strains harbored these genes. The fluoroquinolone-resistant Aeromonas spp. exhibited higher cytotoxicity than fluoroquinolone-sensitive, virulent Aeromonas spp. to rat epithelial cells.  相似文献   

15.
An understanding of why certain Acinetobacter species are more successful in causing nosocomial infections, transmission and epidemic spread in healthcare institutions compared with other species is lacking. We used genomic, phenotypic and virulence studies to identify differences between Acinetobacter species. Fourteen strains representing nine species were examined. Genomic analysis of six strains showed that the A. baumannii core genome contains many genes important for diverse metabolism and survival in the host. Most of the A. baumannii core genes were also present in one or more of the less clinically successful species. In contrast, when the accessory genome of an individual A. baumannii strain was compared to a strain of a less successful species (A. calcoaceticus RUH2202), many operons with putative virulence function were found to be present only in the A. baumannii strain, including the csu operon, the acinetobactin chromosomal cluster, and bacterial defence mechanisms. Phenotype microarray analysis showed that compared to A. calcoaceticus (RUH2202), A. baumannii ATCC 19606T was able to utilise nitrogen sources more effectively and was more tolerant to pH, osmotic and antimicrobial stress. Virulence differences were also observed, with A. baumannii ATCC 19606T, A. pittii SH024, and A. nosocomialis RUH2624 persisting and forming larger biofilms on human skin than A. calcoaceticus. A. baumannii ATCC 19606T and A. pittii SH024 were also able to survive in a murine thigh infection model, whereas the other two species were eradicated. The current study provides important insights into the elucidation of differences in clinical relevance among Acinetobacter species.  相似文献   

16.
Phenotypicaly identified Aeromonas strains (n=119) recovered mainly from diseased fish were genetically re-identified and the concordance between the results was analysed. Molecular characterization based on the GCAT genus specific gene showed that only 90 (75.6%) strains belonged to the genus Aeromonas. The 16S rDNA-RFLP method identified correctly most of the strains with the exception of a few that belonged to A. bestiarum, A. salmonicida or A. piscicola. Separation of these 3 species was correctly assessed with the rpoD gene sequences, which revealed that 5 strains with the RFLP pattern of A. salmonicida belonged to A. piscicola, as did 1 strain with the pattern of A. bestiarum. Correct phenotypic identification occurred in only 32 (35.5%) of the 90 strains. Only 14 (21.8%) of the 64 phenotypically identified A. hydrophila strains belonged to this species. However, coincident results were obtained in 88% (15/17) of the genetically identified A. salmonicida strains. Phenotypic tests were re-evaluated on the 90 genetically characterized Aeromonas strains and there were contradictions in the species A. sobria for a number of previously published species-specific traits. After genetic identification, the prevailing species were A. sobria, A. salmonicida, A. bestiarum, A. hydrophila, A. piscicola and A. media but we could also identify a new isolate of the recently described species A. tecta. This work emphasizes the need to rely on the 16S rDNA-RFLP method and sequencing of housekeeping genes such as rpoD for the correct identification of Aeromonas strains.  相似文献   

17.
The genus Argiope represents a collection of morphologically diverse orb-weaving spiders with a cosmopolitan distribution. Argiope dang and A. mangal are two Southeast Asian species that share remarkably similar morphological characteristics congeneric to the A. aetherea species group. However, in previous investigations, molecular data have not been used for the taxonomic categorization of A. dang and A. mangal. Additionally, gene flow between populations of A. dang and of A. mangal in their natural habitats has not been adequately studied. In the present study, mitochondrial 16S, COI and COII markers were used in addition to the nuclear H3 gene to elucidate the relationships between A. dang, A. mangal and various congeners within the A. aetherea species group. The haplotype diversity of A. dang and A. mangal was also investigated. Based on our molecular results, the A. aetherea species group was composed of three genetic lineages: (i) [A. dang - (A. radon - A. picta)] - [A. modesta - A. aetherea]; (ii) A. mangal; and (iii) [(A. jinghongensis - A. aetheroides) - A. versicolor]. Haplotype analyses revealed a lack of gene flow between A. mangal populations in Peninsular Malaysia and those in Singapore. Populations of A. dang showed isolation-by-distance throughout the range of the species from Laos to Singapore. In this study for the first time, genetic data of A. mangal were reported for specimens collected from its type locality, Singapore. Four new distribution records were also reported: A. dang in Peninsular Malaysia and Cambodia; A. modesta in Bali, Indonesia; and A. jinghongensis in Peninsular Malaysia.  相似文献   

18.
19.
《Insect Biochemistry》1986,16(1):273-279
Extracts from post-vitellogenic ovaries of Musca domestica, Aedes atropalpus and Drosphila melanogaster were examined for the ability to inhibit the vitellogenic phase of growth in newly emerged A. atropalpus and D. melanogaster adult females. All extracts were inhibitory in A. atropalpus. D. melanogaster females were less sensitive than A. atropalpus females, only showing inhibition at a two-fold greater concentration of M. domestica extract. The titre of oostatic hormone in A. atropalpus ovaries correlated with the decline in ecdysteroid synthesis by these ovaries. A. atropalpus ovaries containing post-vitellogenic follicles were shown to inhibit ovarian ecdysteroid synthesis in vitro by vitellogenic ovaries of both A. atropalpus and D. melanogaster. D. melanogaster ovaries were not capable of eliciting such an inhibition in vitro, at least with the numbers of ovaries utilized in our experiments.  相似文献   

20.
The genus Arcobacter is composed of 17 species which have been isolated from various sources. Of particular interest are A. butzleri, A. cryaerophilus, and A. skirrowii, as these have been associated with human cases of diarrhea, the probable transmission routes being through the ingestion of contaminated drinking water and food. To date, only limited studies of virulence traits in this genus have been undertaken. The present study used 60 Arcobacter strains isolated from different sources, representing 16 of the 17 species of the genus, to investigate their ability to adhere to and invade the human intestinal cell line Caco-2. In addition, the presence of five putative virulence genes (ciaB, cadF, cj1349, hecA, and irgA) was screened for in these strains by PCR. All Arcobacter species except A. bivalviorum and Arcobacter sp. strain W63 adhered to Caco-2 cells, and most species (10/16) were invasive. The most invasive species were A. skirrowii, A. cryaerophilus, A. butzleri, and A. defluvii. All invasive strains were positive for ciaB (encoding a putative invasion protein). Other putative virulence genes were present in other species, i.e., A. butzleri (cadF, cj1349, irgA, and hecA), A. trophiarum (cj1349), A. ellisii (cj1349), and A. defluvii (irgA). No virulence genes were detected in strains which showed little or no invasion of Caco-2 cells. These results indicate that many Arcobacter species are potential pathogens of humans and animals.  相似文献   

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