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1.
Bioresour Technol ; 310: 123419, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32361200

RESUMO

A vertical flow constructed wetland (VFCW) packed with the different substrates was designed to remediate the antibiotics in the wastewater. Zeolite (CW-Z) paralleled with Manganese (Mn) ore (CW-M) and biochar (CW-C) were used to enhance the synchronous removal of ciprofloxacin hydrochloride (CIPH), sulfamethazine (SMZ) and nitrogen (N) from the wastewater. The result indicated that CW-M had a significant potential to remove CIPH (93%), SMZ (69%), TN (71%), NH4+-N (94%) and NO3--N (94%) across all the treatments. The abundance of amoA, nirK and nirS genes are dramatically higher in CW-M and CW-C, while CW-C inhibited the production of quinolone resistance genes. Results showed that different substrates could affect the microbial diversity and structure. The addition of Mn ore to the water led to an improved abundance of nitrogen-related phyla. Overall, Mn ore has a considerable potential to simultaneously remove antibiotics and N in VFCWs.

2.
Chemosphere ; 244: 125556, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050346

RESUMO

Carbon source and dissolved oxygen are the critical factors which sustain the stable redox environment for the microbes to implement the removal of nitrogen and organics in vertical flow constructed wetlands (VFCWs). The effect mechanisms of the COD/N ratios in intermittently aerated VFCWs are needed to be investigated in order to increase the synchronous removal efficiency of pollutants. In this study, the combined effects of COD/N ratios (3, 6, 12) and intermittent aeration in VFCWs on pollutant removal, microbial communities and related function genes were studied. The results showed the increase of COD/N ratios from 3 to 12 enhanced the removal efficiency of TN, NO3--N and COD. The removals of NH4+-N decreased as the COD/N ratio increased. The optimal removals of TN (87.65%), NH4+-N (93.20%), NO3--N (80.80%) and COD (73.93%) were obtained in VFCW2 (COD/N ratios was 6). Illumina Miseq High-throughput sequencing analysis showed that high COD/N ratios increased the richness and diversity of microbial communities. The absolute abundance of nirK, nosZ, nirS, amoA, nxrA, and anammox bacterial 16S rRNA presented various changes under the different ratios of COD/N. The increase of COD/N ratios enhanced the copy numbers of nirS, nirK and nosZ, which participate in denitrification process. High COD/N ratios (6 and 12) were in favor of Actinobacteria, Firmicutes and Chloroflexi, which mainly play important roles in the process of denitrification. This paper implies that the combination of carbon source and aeration is necessary to sustain high microbial activities during pollutant removal in VFCWs.


Assuntos
Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Áreas Alagadas , Bactérias , Análise da Demanda Biológica de Oxigênio , Carbono , Desnitrificação , Oxigênio , RNA Ribossômico 16S
3.
Plant Dis ; 104(1): 255-259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613189

RESUMO

Acidovorax citrulli is the causal agent of bacterial fruit blotch (BFB), a serious threat to cucurbit fruit and seed production worldwide. In recent years, the BFB has spread to many areas of China, mainly via the inadvertent distribution of contaminated commercial seeds. To assess the prevalence of seedborne A. citrulli in commercial watermelon and other cucurbitaceous seedlots in China, a 9-year survey was conducted between 2010 and 2018. A total of 4,839 seedlots of watermelon and other cucurbitaceous species were collected from 13 major seed production areas of China and tested by a semiselective media-based colony PCR technique for A. citrulli. Overall, A. citrulli was detected in 18.00% (871/4,839) of all cucurbitaceous seedlots. The bacterium was detected in 21.59% (38/176), 19.19% (33/172), 23.44% (214/913), 40.76% (247/606), 13.28% (85/640), 15.40% (95/617), 13.25% (73/551), 8.03% (48/598), and 6.71% (38/566) of all commercial seedlots tested from the 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, and 2018 growing seasons, respectively. Additionally, the prevalence of A. citrulli in cucurbit seedlots was determined for different seed production areas. The prevalence of A. citrulli in cucurbitaceous seedlots produced in Xinjiang, Gansu, Ningxia, Inner Mongolia, and 9 other provinces was 18.76% (582/3103), 26.34% (103/391), 21.47% (82/382), 11.11% (14/126), and 10.75% (90/837), respectively. This is the first survey for A. citrulli in commercial cucurbit seeds in China, and the relatively high prevalence suggests that commercial seeds represent a substantial source of primary inoculum that can threaten cucurbit seed and fruit production in China.


Assuntos
Comamonadaceae , Cucurbitaceae , Sementes , China , Comamonadaceae/fisiologia , Cucurbitaceae/microbiologia , Doenças das Plantas/microbiologia , Sementes/microbiologia
4.
Int J Biol Macromol ; 145: 325-331, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31843609

RESUMO

Structural modification of starch using efficient α-amylases to improve its properties is an established method in the starch industry. In our previous research, the novel maltogenic α-amylase CoMA that catalyzes multi-molecular reactions has been identified. In this study, the impact of CoMA on the structure and retrogradation properties of potato starch was evaluated. CoMA cleaves internal starch chains to change the proportion of amylose and amylopectin in starch. Following treatment, visible pores and microporous on the surface of starch granules were observed from SEM analysis. CoMA modification led to increased insoluble blue complex formation and hydrolysis to shorten the outer chains, which was found to reduce the development rate of starch according to network interactions from the dynamic rheological analysis. Furthermore, maltose accumulation with water competition was also deduced to be involved in the inhibition of retrogradation. Its activities in the cleavage of internal starch granules, shortening of outer chains of starch, and maltose formation make CoMA a powerful agent for the inhibition of starch retrogradation with a very low effective dose of 0.5 mg/kg, which may find potential applications in the starch processing industry.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31660782

RESUMO

Objectives: To study the epidemiological characteristics of malaria and the effects of comprehensive malaria control implementation in Yantai, as well as to provide a scientific basis for future malaria elimination. Materials and Methods: A retrospective analysis was conducted to explore the epidemiological changes and prevention effects in Yantai from 1951 to 2017. The malaria data before 2004 were collected from paper-based annual reports, and data after 2004 came from the Infectious Diseases Information Reporting Management System. Results: A total of 81,286 malaria cases were identified in Yantai from 1957 to 2017, with two peaks occurring in 1966 (120.93/100,000) and 1970-1972 (366.12/100,000). From 1951 to 2003, the case classification was mainly Plasmodium vivax (99.80%); the first case attributed to Plasmodium falciparum occurred in 2004, and P. falciparum became the main cause of malaria after 2011. All cases reported since 2010 have been imported cases, and the last indigenous case was caused by P. vivax in 2008. A total of 129 imported cases were reported from 2010 to 2017, most of which originated in Africa (93.80%), mainly in men aged 30-49 years (68.28%). From 1951 to 1973, 73,868 cases of malaria were diagnosed with clinical symptoms, and from 1974 to 2017, 818,943 cases in fever patients were diagnosed with blood tests. Conclusions: To achieve the goal of eliminating malaria by 2020, Yantai should continue to strengthen the management of migrant population, including improving malaria surveillance for returnees and immigrants from overseas endemic areas, and continue to increase the training of medical personnel to improve their diagnostic ability.

6.
Phytopathology ; 109(12): 1997-2008, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31454303

RESUMO

Acidovorax citrulli is the causal agent of bacterial fruit blotch, a serious threat to commercial watermelon and melon crop production worldwide. Ferric uptake regulator (Fur) is a global transcription factor that affects a number of virulence-related functions in phytopathogenic bacteria; however, the role of furA has not been determined for A. citrulli. Hence, we constructed an furA deletion mutant and a corresponding complement in the background of A. citrulli strain xlj12 to investigate the role of the gene in siderophore production, concentration of intracellular Fe2+, bacterial sensitivity to hydrogen peroxide, biofilm formation, swimming motility, hypersensitive response induction, and virulence on melon seedlings. The A. citrulli furA deletion mutant displayed increased siderophore production, intracellular Fe2+ concentration, and increased sensitivity to hydrogen peroxide. In contrast, biofilm formation, swimming motility, and virulence on melon seedlings were significantly reduced in the furA mutant. As expected, complementation of the furA deletion mutant restored all phenotypes to wild-type levels. In accordance with the phenotypic results, the expression levels of bfrA and bfrB that encode bacterioferritin, sodB that encodes iron/manganese superoxide dismutase, fliS that encodes a flagellar protein, hrcN that encodes the type III secretion system (T3SS) ATPase, and hrcC that encodes the T3SS outer membrane ring protein were significantly downregulated in the A. citrulli furA deletion mutant. In addition, the expression of feo-related genes and feoA and feoB was significantly upregulated in the furA mutant. Overall, these results indicated that, in A. citrulli, FurA contributes to the regulation of the iron balance system, and affects a variety of virulence-related traits.


Assuntos
Proteínas de Bactérias , Citrullus , Comamonadaceae , Proteínas Repressoras , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Citrullus/microbiologia , Comamonadaceae/genética , Comamonadaceae/patogenicidade , Doenças das Plantas/microbiologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Virulência/genética
7.
ISME J ; 13(9): 2223-2235, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31065029

RESUMO

Myxobacterial predation on bacteria has been investigated for several decades. However, their predation on fungi has received less attention. Here, we show that a novel outer membrane ß-1,6-glucanase GluM from Corallococcus sp. strain EGB is essential for initial sensing and efficient decomposition of fungi during predation. GluM belongs to an unstudied family of outer membrane ß-barrel proteins with potent specific activity up to 24,000 U/mg, whose homologs extensively exist in myxobacteria. GluM was able to digest fungal cell walls efficiently and restrict Magnaporthe oryzae infection of rice plants. Genetic complementation with gluM restored the fungal predation ability of Myxococcus xanthus CL1001, which was abolished by the disruption of gluM homolog oar. The inability to prey on fungi with cell walls that lack ß-1,6-glucans indicates that ß-1,6-glucans are targeted by GluM. Our results demonstrate that GluM confers myxobacteria with the ability to feed on fungi, and provide new insights for understanding predator-prey interactions. Considering the attack mode of GluM, we suggest that ß-1,6-glucan is a promising target for the development of novel broad-spectrum antifungal agents.


Assuntos
/enzimologia , Proteínas de Bactérias/metabolismo , Fungos/química , Glicosídeo Hidrolases/metabolismo , Myxococcus xanthus/enzimologia , Proteínas de Bactérias/genética , Glucanos/metabolismo , Glicosídeo Hidrolases/genética , Myxococcus xanthus/fisiologia
8.
Int J Mol Sci ; 20(4)2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781446

RESUMO

Chinese chestnut (Castanea mollissima Blume) can be infested by Dryocosmus kuriphilus Yasumatsu, resulting in gall formation and yield losses. Research on the control of gall wasps using genomics approaches is rarely reported. We used RNA-seq to investigate the dynamic changes in the genes of a chestnut species (C. mollissima B.) during four gall-formation stages caused by D. kuriphilus. A total of 21,306 genes were annotated by BLAST in databases. Transcriptome comparison between different gall-formation stages revealed many genes that were differentially expressed compared to the control. Among these, 2410, 7373, 6294, and 9412 genes were differentially expressed in four gall-formation stages: initiation stage (A), early growth stage (B), late growth stage (C), and maturation stage (D), respectively. Annotation analysis indicated that many metabolic processes (e.g., phenylpropanoid biosynthesis, secondary metabolism, plant⁻pathogen interaction) were affected. Interesting genes encoding putative components of signal transduction, stress response, and transcription factors were also differentially regulated. These genes might play important roles in response to D. kuriphilus gall formation. These new data on the mechanism by which D. kuriphilus infests chestnuts could help improve chestnut resistance.


Assuntos
Fagaceae/genética , Fagaceae/parasitologia , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Vespas/fisiologia , Animais , Regulação da Expressão Gênica de Plantas , Oxirredução , Folhas de Planta/parasitologia , Tumores de Planta/parasitologia , Reprodutibilidade dos Testes , Metabolismo Secundário/genética , Transcrição Genética
9.
Plant Dis ; 102(12): 2511-2518, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30320533

RESUMO

Peach (Prunus persica (L.) Batsch) is produced locally in Yangshan, Wuxi City, China. In recent years, a widespread shoot blight has been observed in many peach orchards of Yangshan that kills the twigs and results in high losses in fruit production. Disease incidences ranged from 10 to 20% in the affected orchards and, in extreme cases, 40% of the trees were affected. Shoot blight of peach is caused by a fungus, previously identified as Phomopsis amygdali. Between 2014 and 2015, samples were collected four times from three peach orchards located in Yangshan to understand the etiology of shoot blight. Interestingly, two types of shoot blight symptoms were observed: one characterized by necrotic lesions with rings and one without rings. Based on conidial morphology, cultural characteristics, and analysis of nucleotide sequences of three genomic regions (the internal transcribed spacer region, a partial sequence of the ß-tubulin gene, and the translation elongation factor 1-α), isolates were identified as P. amygdali and Botryosphaeria dothidea. Remarkably, most of the P. amygdali isolates were recovered from twigs showing necrotic lesions without rings. In contrast, most of the B. dothidea isolates were recovered from twigs with rings in the necrotic lesions. Correlations among pathogens, sampling regions, and disease symptoms were noted, and growth rates of these pathogens were characterized. Pathogenicity tests showed that B. dothidea isolates could induce necrotic lesions with rings but P. amygdali isolates could only induce necrotic lesions. Moreover, the B. dothidea isolates exhibited higher levels of virulence than P. amygdali isolates on the peach twig. Additionally, high frequencies of detection of both P. amygdali and B. dothidea from buds indicated that buds may be the primary site of fungal invasion. Cankers and necrotic twigs may also serve as infection courts. Our results suggest that B. dothidea and P. amygdali are the common causal agents of peach shoot blight in Yangshan, China. This finding provides a basis for the development of effective management strategies.


Assuntos
Ascomicetos/isolamento & purificação , Doenças das Plantas/microbiologia , Prunus persica/microbiologia , Ascomicetos/genética , Ascomicetos/patogenicidade , China , Filogenia , Brotos de Planta/microbiologia , Virulência
10.
PLoS One ; 13(7): e0200445, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29995940

RESUMO

Tongcheng (TC) and Yorkshire (YK) are two pig breeds with distinctive muscle morphology. Porcine microRNAome (miRNAome) of the longissimus muscle during five developmental stages (40, 55, 63, 70, and 90 days post coitum (dpc)) was explored by Solexa sequencing in the present study to find miRNAs involved in the different regulation of skeletal muscle development between the two breeds. A total of 320 known porcine miRNAs, 64 miRNAs corresponding to other mammals, and 224 potentially novel miRNAs were identified. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) suggested that the factor "pig breed" affected the miRNA expression profiles to a lesser extent than the factor "developmental stage". Fifty-seven miRNAs were differentially expressed (DE) between the neighbor developmental stages in TC and 45 such miRNAs were found in YK, 34 in common; there were more down-regulated stage-DE miRNAs than up-regulated. And a total of 23, 30, 12, 6, and 30 breed-DE miRNAs between TC and YK were identified at 40, 55, 63, 70, and 90 dpc, respectively, which were mainly involved in cellular protein modification process, protein transport, and metabolic process. As the only highly expressed breed-DE miRNA found in no less than four developmental stages, and also a stage-DE miRNA found both in TC and YK, miR-499-5p could bind the 3'-UTR of a myofibrillogenesis regulator, destrin/actin depolymerizing factor (DSTN), as validated in dual luciferase reporter assay. The results suggested that miR-499-5p possibly play a noteworthy role in the breed-distinctive porcine muscle fiber development associated with the regulation of DSTN.


Assuntos
Músculos do Dorso/crescimento & desenvolvimento , Músculos do Dorso/metabolismo , MicroRNAs/metabolismo , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/metabolismo , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , RNA Mensageiro/metabolismo , Especificidade da Espécie
11.
Genome Announc ; 6(20)2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29773614

RESUMO

Dickeya fangzhongdai DSM 101947T was isolated from pear trees (Pyrus pyrifolia) in Zhejiang Province, China, and is the causal agent of bleeding canker, a devastating disease of pear trees. Here, we provide the complete genome sequence of this bacterium, which has a 5,027,163-bp-long genome, including 4,375 protein-coding genes and 100 RNA genes. This strain possesses a number of genes encoding virulence factors of pathogens.

12.
Front Chem ; 6: 72, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29616217

RESUMO

Thermal expansion and magnetostriction, the strain responses of a material to temperature and a magnetic field, especially properties at low temperature, are extremely useful to study electronic and phononic properties, phase transitions, quantum criticality, and other interesting phenomena in cryogenic engineering and materials science. However, traditional dilatometers cannot provide magnetic field and ultra-low temperature (<77 K) environment easily. This paper describes the design and test results of thermal expansion and magnetostriction at cryogenic temperature using the strain gauge method based on a Physical Properties Measurements System (PPMS). The interfacing software and automation were developed using LabVIEW. The sample temperature range can be tuned continuously between 1.8 and 400 K. With this PPMS-aided measuring system, we can observe temperature and magnetic field dependence of the linear thermal expansion of different solid materials easily and accurately.

13.
Funct Integr Genomics ; 18(2): 195-209, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29322263

RESUMO

Myogenesis is accompanied by a number of changes in gene expression in mammals, and the transcriptional events that underlie these processes have not been yet fully elucidated. In this study, RNA-seq was used to comprehensively compare the transcription profiles of skeletal muscle between Tongcheng (TC) and Yorkshire (YK) pigs at 40, 55, 63, 70, and 90 days of gestation. One thousand three hundred seventeen and 691 differentially expressed genes (DEGs) were detected in TC and YK, respectively, among which 321 DEGs were shown to be common in TC and YK. STEM (Time-series Expression Miner) analysis revealed different gene expression profiles between the two breeds. One thousand six hundred seventy-seven genes showed significant differential expression between TC and YK at the identical stages, while three genes were found to be common in all comparisons. A total of 3185 new putative transcripts were also predicted. Several gene expression profiles were further validated by qRT-PCR. Fifty-five dpc (days post coitum) was suggested to be the key stage to contribute developmental differences between TC and YK. PTEN, EP300, ENSSSCG00000004979 (Myosin 9A), CDK14, IRS1, PPP1CC, and some ribosomal proteins were suggested to be the key candidate genes for elucidating the developmental differences between the two breeds. In conclusion, we constructed comprehensive high-resolution gene expression maps of these two pig breeds, which not only provides an in-depth understanding of the dynamics of transcriptional regulation during myogenesis in this study, but also would facilitate the elucidation of molecular mechanisms underlying myogenesis in the future studies.


Assuntos
Músculo Esquelético/metabolismo , Suínos/genética , Transcriptoma , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Desenvolvimento Muscular , Músculo Esquelético/embriologia , Suínos/embriologia
14.
Korean J Parasitol ; 55(5): 555-559, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29103271

RESUMO

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China (114-112°E, 34-38°N), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.


Assuntos
Roedores/parasitologia , Trombiculidae , Animais , Arvicolinae , China , Cricetulus , Camundongos , Murinae , Ratos , Estações do Ano , Trombiculidae/classificação
15.
Phytopathology ; 107(6): 654-661, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28421913

RESUMO

The type VI secretion system (T6SS) plays a major role in mediating interbacterial competition and might contribute to virulence in plant pathogenic bacteria. However, the role of T6SS in Erwinia amylovora remains unknown. In this study, 33 deletion mutants within three T6SS clusters were generated in E. amylovora strain NCPPB1665. Our results showed that all 33 mutants displayed reduced antibacterial activities against Escherichia coli as compared with that of the wild-type (WT) strain, indicating that Erwinia amylovora T6SS are functional. Of the 33 mutants, 19 exhibited reduced virulence on immature pear fruit as compared with that of the WT strain. Among them, 6, 1, and 12 genes belonged to T6SS-1, T6SS-2, and T6SS-3 clusters, respectively. Interestingly, these 19 mutants also produced less amylovoran or levan or both. These findings suggest that E. amylovora T6SS play a role in bacterial competition and virulence possibly by influencing exopolysaccharide production.


Assuntos
Erwinia amylovora , Frutanos/metabolismo , Doenças das Plantas/microbiologia , Polissacarídeos Bacterianos/metabolismo , Pyrus/microbiologia , Sistemas de Secreção Tipo VI/metabolismo , Erwinia amylovora/genética , Erwinia amylovora/patogenicidade , Erwinia amylovora/fisiologia , Frutas/microbiologia , Deleção de Sequência , Sistemas de Secreção Tipo VI/genética , Virulência
16.
Plant Dis ; 101(10): 1746-1752, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30676919

RESUMO

Bacterial leaf blight (BLB) has caused severe yield losses in cantaloupe (Cucumis melo L.) in the major melon-growing regions of China since the beginning of the twentieth century. Historically, Pseudomonas syringae pv. lachrymans was considered to be the causal agent of BLB of cantaloupe and angular leaf spot of cucumber. In the process of characterizing bacteria isolated from cantaloupe, we observed that putative P. syringae pv. lachrymans yielded negative results in P. syringae pv. lachrymans-specific PCR assays. This suggested that the P. syringae pv. lachrymans-like strains from cantaloupe were distinct from those recovered from cucumber. To investigate the differences between P. syringae pv. lachrymans-like strains isolated from cantaloupe and cucumber, 13 P. syringae strains isolated from cantaloupe [12 from China and 1 from Zimbabwe (NCPPB2916)] and 7 additional P. syringae reference strains were analyzed by catabolic profiling, phylogenetic analysis by multilocus sequence analysis (MLSA) and pathogenicity tests on cantaloupe leaflets. Catabolic profiling and MLSA based on 10 housekeeping genes and 2 hypersensitive response and pathogenicity (hrp) genes allowed us to differentiate strains isolated from cantaloupe and cucumber. Pseudomonas syringae pv. lachrymans strains isolated from cucumber clustered with genomospecies 2, and 13 P. syringae strains isolated from cantaloupe belonged to genomospecies 1. While all cantaloupe strains were closely related to P. syringae pv. aptata, they could be differentiated from this pathovar based on metabolic tests and MLSA. Pathogenicity tests showed that all strains isolated from cantaloupe and cucumber were only pathogenic on their original hosts. Based on these observations we conclude that P. syringae pv. lachrymans strains recovered from cantaloupe in China represent a novel phylotype.


Assuntos
Cucumis melo , Pseudomonas syringae , China , Cucumis melo/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Pseudomonas syringae/classificação , Pseudomonas syringae/genética , Pseudomonas syringae/fisiologia , Especificidade da Espécie , Zimbábue
17.
Phys Chem Chem Phys ; 18(30): 20276-80, 2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27411397

RESUMO

Cubic NaZn13-type La(Fe1-xCox)11.4Al1.6 compounds were synthesized and extensively explored through crystal structure and magnetization analyses. By optimizing the chemical composition, the isotropic abnormal properties of excellent zero and giant negative thermal expansion in a pure form were both found at different temperature ranges through room temperature. Moreover, the temperature regions with the remarkable abnormal thermal expansion (ATE) properties have been broadened which are controlled by the dM/dT. The present study demonstrates that the ATE behavior mainly depends on special structural and magnetic properties. These diverse properties suggest the high potential of La(Fe1-xCox)11.4Al1.6 for the development of abnormal expansion materials.

18.
J Arthropod Borne Dis ; 10(2): 211-21, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27308279

RESUMO

BACKGROUND: The aim of the current study was to develop a marking technique as an internal marker to mark post blood meal mosquitoes by using stable phosphate isotope (32)P and determine the optimal concentration of it. METHODS: An isotonic physiological saline solution, containing different concentration of radioactive isotope (32)P-labeled disodium phosphate (Na2H(32)PO4) was injected into rabbits via the jugular vein in the laboratory. Emerged Cx. pipiens were marked after feeding on rabbit. At the same time, the labeled conditions of emerged Cx. pipiens were also measured by placing feces of No. 6 rabbit into containers with mosquito larvae and pupae inside. RESULTS: According to the label condition of Cx. pipiens after taking blood and the effect of different dosage Na2H(32)PO4 on rabbit health, the optimal concentration of radioactive isotope was determined, that is, 0.1211 mCi/kg. By placing feces of No. 6 rabbit into containers with mosquito larvae and pupae inside, the emerged mosquitoes were also labeled. Therefore, feeding mosquitoes on the animal injected with radioactive Na2H(32)PO4 was more practical for detecting and tracing mosquitoes. CONCLUSION: The method was less time-consuming, more sensitive and safer. This marking method will facilitate post-bloodmeal studies of mosquitoes and other blood-sucking insects.

19.
Int J Syst Evol Microbiol ; 66(8): 2831-2835, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27045848

RESUMO

Gram-stain-negative, pectinolytic bacteria were repeatedly isolated from pear trees displaying symptoms of bleeding canker in China. Three strains, JS5T, LN1 and QZH3, had identical 16S rRNA gene sequences that shared 99 % similarity to the type strain of Dickeya dadantii. Phylogenetic analysis of strains JS5T, LN1 and QZH3 with isolates representing all species of the genus Dickeya and related Pectobacterium species supported their affiliation to Dickeya. Multi-locus sequence typing employing concatenated sequences encoding recA, fusA, gapA, purA, rplB, dnaX and the intergenic spacer illustrated a phylogeny which placed strains JS5T, LN1 and QZH3 as a distinct clade, separate from all other species of the genus Dickeya. Average nucleotide identity values obtained in comparison with all species of the genus Dickeya supported the distinctiveness of strain JS5T within the genus Dickeya. Additionally, all three strains were phenotypically distinguished from other species of the genus Dickeya by failing to hydrolyse casein, and by producing acids from (-)-d-arabinose, (+)melibiose, (+)raffinose, mannitol and myo-inositol, but not from 5-keto-d-gluconate or ß-gentiobiose. The name Dickeya fangzhongdai sp. nov. is proposed to accommodate these strains; the type strain is JS5T (=CGMCC 1.15464T=DSM 101947T).


Assuntos
Enterobacteriaceae/classificação , Filogenia , Doenças das Plantas/microbiologia , Pyrus/microbiologia , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Fenótipo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Phys Chem Chem Phys ; 17(46): 30999-1003, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26549525

RESUMO

Recently, La(Fe,Si)13-based compounds have attracted much attention due to their isotropic and tunable abnormal thermal expansion (ATE) properties as well as bright prospects for practical applications. In this research, we have prepared cubic NaZn13-type carbon-doped La(Fe,Si)13 compounds by the arc-melting method, and their ATE and magnetic properties were investigated by means of variable-temperature X-ray diffraction, strain gauge and the physical property measurement system (PPMS). The experimental results indicate that both micro and macro negative thermal expansion (NTE) behaviors gradually weaken with the increase of interstitial carbon atoms. Moreover, the temperature region with the most remarkable NTE properties has been broadened and near zero thermal expansion (NZTE) behavior occurs in the bulk carbon-doped La(Fe,Si)13 compounds.

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