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1.
Ecotoxicol Environ Saf ; 195: 110375, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32200142

RESUMO

Microbial immobilization is a novel and environmentally friendly technology that uses microbes to reduce metal availability in soil and accumulation of heavy metals in plants. We used urea agar plates to isolate urease-producing bacteria from the rhizosphere soil of pakchoi in Cd- and Pb-contaminated farmland and investigated their effects on Cd and Pb accumulation in pakchoi and the underlying mechanisms. The results showed that two urease-producing bacteria, Bacillus megaterium N3 and Serratia liquefaciens H12, were identified by screening. They had higher ability to produce urease (57.5 ms cm-1 min-1 OD600-1 and 76.4 ms cm-1 min-1 OD600-1, respectively). The two strains allowed for the immobilization of Cd and Pb by extracellular adsorption, bioprecipitation, and increasing the pH (from 6.94 to 7.05-7.09), NH4+ content (69.1%-127%), and NH4+/NO3- ratio (from 1.37 to 1.67-2.11), thereby reducing the DTPA-extractable Cd (35.3%-58.8%) and Pb (37.8%-62.2%) contents in the pakchoi rhizosphere soils and the Cd (76.5%-79.7%) and Pb (76.3%-83.5%) contents in the leaves (edible tissue) of pakchoi. The strains were highly resistant to heavy metal toxicity; produced IAA, siderophores and abscisic acid; and increased the NH4+/NO3- ratio, which might be related to the two strains protectiing pakchoi against the toxic effect of Cd and Pb and increasing pakchoi biomass. Thus, the results were supposed to strain resources and a theoretical basis for the remediation of Cd- and Pb-contaminated farmlands for the safe production of vegetables.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32079120

RESUMO

The water-level fluctuation zone (WLFZ) is a transitional zone between terrestrial and aquatic ecosystems. Plant communities that are constructed artificially in the WLFZ can absorb and retain nutrients such as nitrogen (N) and phosphorus (P). However, the microbial community composition and function associated with this process have not been elucidated. In this study, four artificially constructed plant communities, including those of herbs (Cynodon dactylon and Chrysopogon zizanioides), trees (Metasequoia glyptostroboides), and shrubs (Salix matsudana) from the newly formed WLFZ of the Danjiangkou Reservoir were evaluated. The bacterial community compositions were analyzed by 16S rRNA gene sequencing using a MiSeq platform, and the functions of these communities were assessed via Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis. The results showed that the bacterial communities primarily comprised 362 genera from 24 phyla, such as Proteobacteria, Acidobacteria, Actinobacteria, and Gemmatimonadetes, showing the richness of the community composition. Planting altered the bacterial community composition, with varying effects observed among the different plant types. The bacterial community functional analysis revealed that these bacteria were primarily associated with six biological metabolic pathway categories (e.g., metabolism, genetic information processing, and environmental information processing) with 34 subfunctions, showing the richness of community functions. The planting of M. glyptostroboides, S. matsudana, and C. dactylon improved the metabolic capabilities of bacterial communities. N- and P-cycling gene analysis showed that planting altered the N- and P-cycling metabolic capacities of soil bacteria. The overall N- and P-metabolic capacity was highly similar between C. dactylon and C. zizanioides samples and between S. matsudana and M. glyptostroboides samples. The results of this study provide a preliminary analysis of soil bacterial community structure and function in the WLFZ of the Danjiangkou Reservoir and provides a reference for vegetation construction in this zone.

3.
Arch Microbiol ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32067064

RESUMO

Soil microbes play important roles in plant growth and in the biogeochemical cycling of earth's elements. However, the structure and functions of the microbial community associated with the growth of second-generation energy crops, such as Miscanthus, remain unclear. Thus, in this study, the composition and function of the bacterial and fungal communities associated with Miscanthus cultivation were analyzed by MiSeq sequencing combined with PICRUSt and FUNGUIld analyses. The results of community composition and diversity index analyses showed that Miscanthus cultivation significantly altered the bacterial and fungal community composition and reduced bacterial and fungal diversity. In addition, Miscanthus cultivation increased the soil organic matter (SOM) and total nitrogen (TN) contents. The correlation analysis between microbial community composition and environmental factors indicated that SOM and TN were the most important factors affecting bacterial and fungal communities. Miscanthus cultivation could enrich the abundances of Pseudomonas, Rhizobium, Luteibacter, Bradyrhizobium, Phenylobacterium and other common plant-promoting bacteria, while also increasing Cladophialophora, Hymenula, Magnaporthe, Mariannaea, etc., which predicted corresponded to the saprotrophic, plant pathogenic, and pathotrophic trophic modes. The PICRUSt predictive analysis indicated that Miscanthus cultivation altered the metabolic capabilities of bacterial communities, including the metabolism of carbon, nitrogen, and phosphorus cycle. In addition, FUNGUIld analysis indicated that Miscanthus cultivation altered the fungal trophic mode. The effects of Miscanthus on the communities and function of bacteria and fungi varied among Miscanthus species. Miscanthus specie Xiangdi NO 1 had the greatest impact on soil bacterial and fungal communities, whereas Miscanthus specie Wujiemang NO 1 had the greatest impact on soil bacteria and fungi functions. The results of this study provide a reference for the composition and function of microbial communities during the growth of Miscanthus.

4.
Arch Microbiol ; 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894394

RESUMO

Network analysis has contributed to studies of the interactions of microorganisms and the identification of key populations. However, such analysis has rarely been conducted in the study of reservoir bacterioplankton communities. This study investigated the bacterioplankton community composition in the surface water of the Danjiangkou Reservoir using the Illumina MiSeq sequencing platform. We observed that the bacterioplankton community primarily consisted of 27 phyla and 336 genera, including Actinobacteria, Proteobacteria, and Bacteroidetes, demonstrating the richness of the community composition. Redundancy analysis of the bacterioplankton communities and environmental variables showed that the total nitrogen (TN), pH, chemical oxygen demand (COD), and permanganate index (CODMn) were important factors affecting the bacterioplankton distribution. Network analysis was performed using the relative abundances of bacterioplankton based on the phylogenetic molecular ecological network (pMEN) method. The connectivity of node i within modules (Zi), the connectivity of node i among modules (Pi), and the number of key bacteria were high at the Taizishan and Heijizui sites, which were associated with higher TN contents than at the other sites. Among the physicochemical properties of water, TN, ammonia nitrogen (NH4-N), pH, COD, and dissolved oxygen (DO) might have great influences on the functional units of the bacterial communities in bacterioplankton molecular networks. This study improves the understanding of the structure and function of bacterioplankton communities in the Danjiangkou Reservoir.

5.
Huan Jing Ke Xue ; 40(11): 5133-5141, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854583

RESUMO

To investigate the diversity of culturable bacteria and heavy metal-immobilizing bacteria in vegetable rhizosphere soil with high concentrations of heavy metals and explore these microbial resources, two samples of Italian lettuce rhizosphere soil with high heavy metal concentration (HY) and low heavy metal concentration (DK) were collected from Xinxiang, Henan Province. The diversity of culturable bacteria and heavy metal-immobilizing bacteria in the rhizosphere soil of lettuce was compared by culturable separation technology and a solution adsorption experiment. The enhancement of Cd and Pb immobilization and lettuce growth by the strains was also investigated in a hydroponic experiment. The results showed that 400 strains belonging to 3 phyla and 14 genera were isolated from the HY sample, with ß-Proteobacteria being the dominant phylum. Meanwhile, 400 strains belonging to 4 phyla and 30 genera were isolated from the DK sample, with Firmicutes being the dominant phylum. A total of 146 strains had a strong ability to immobilize heavy metal and the Cd and Pb removal rates were greater than 80% in the HY sample; Brevundimonas, Serratia, Arthrobacter, and Pseudarthrobacter were the main genera. However, 44 strains had a strong ability to immobilize heavy metal and the Cd and Pb removal rates were greater than 80% in the DK sample, with Bacillus being the main genus. Compared with the control, inoculation with Serratia liquefaciens HY-22, Bacillus thuringiensis HY-53, and Acinetobacter lwoffii HY-157 significantly increased the dry weight of roots (7.5%-77.6%) and shoots (15.4%-67.2%) of the Italian lettuce and cauliflower lettuce and reduced the contents of Cd (38.7%-66.6%) and Pb (34.7%-62.5%) in roots and shoots of Italian lettuce. In addition, the contents of Cd and Pb in the fresh shoots of Italian lettuce and cauliflower lettuce in the presence of Bacillus thuringiensis HY-53 were lower than the Cd and Pb limits set by national food safety standards. Thus, the results provided strain resources and a theoretical basis for the remediation of Cd-and Pb-contaminated farmlands for the safe production of crops.


Assuntos
Metais Pesados , Poluentes do Solo , Bactérias , Alface , Rizosfera , Solo
6.
Huan Jing Ke Xue ; 40(7): 3339-3346, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854736

RESUMO

The effects of heavy metal contamination on farmland continues to worsen progressively with an increase in anthropogenic activities such as industrial pollution and mining. Excess Cd and Pb in agricultural soils enter the food chain and adversely affect all organisms. Therefore, it is important to find an eco-friendly way to reduce heavy metal accumulation in crops. Based on their heavy metal resistance and growth-promoting characteristics, functional bacterial strains were screened and their effects on growth and heavy metal accumulation in wheat were verified via shaking flask adsorption and sand culture tests. Eighteen functional strains were isolated from the rhizospheric soil of Salvia setaria. Among them, Bacillus megaterium N3 and Serratia liquefaciens H12 were most effective at resisting high Cd (650 mg·L-1) and Pb (2700 mg·L-1) concentrations, and at producing indole-3-acetic acid (IAA) (56.6 mg·L-1and 69.1 mg·L-1, respectively), siderophores, and 1-Amino-1-cyclopropanecarboxylic acid (ACC) deaminase. Static incubation experiments showed that strains N3 and H12 significantly increased the NH4+ concentration and pH, and decreased the Cd (63.1%-73.8%) and Pb (69.1%-81.8%) concentration in solution. In sand cultures, strains N3 and H12 not only increased the dry weight of wheat roots (47.2%-97.4%) and shoots (65.3%-153%) significantly, but also significantly reduced the Cd (49.2%-68.3%) and Pb (27.4%-84.5%) content in wheat roots and shoots. Thus, the results provide strain resources and a theoretical basis for the remediation of Cd- and Pb-contaminated farmlands for the safer production of crops.


Assuntos
Bactérias/isolamento & purificação , Metais Pesados/análise , Microbiologia do Solo , Poluentes do Solo/análise , Triticum/química , Triticum/microbiologia
7.
Front Microbiol ; 10: 1455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316489

RESUMO

Previous analyses of plant growth-promoting bacteria (PGPB) combined with the remediation of heavy metal pollution in soil have largely been performed under potting or greenhouse conditions, and in situ remediation experiments under field conditions have rarely been reported. In this study, the effects of the metal-resistant PGPB Microbacterium oxydans JYC17, Pseudomonas thivervalensis Y1-3-9, and Burkholderia cepacia J62 on soil Cu pollution under rape remediation were studied in the farmland surrounding the Nanjing Jiuhuashan copper mining region in China. Following inoculation treatment for 50 days, the biomasses of the rape inoculated with strains JYC17, Y1-3-9, and J62 increased, and the total amounts of Cu uptake increased by 113.38, 66.26, and 67.91%, respectively, the translocation factor (TF) of rape inoculated with J62 was 0.85, a significant increase of 70.68%, thus improving the Cu remediation efficiency of the rape. Y1-3-9 and J62 affected the bioavailability of Cu in the soil, and the water-soluble Cu contents were increased by 10.13 and 41.77%, respectively, compared with the control. The antioxidant activities in the rape leaves showed that the tested bacteria increased the contents of antioxidant non-enzymatic substances, including ascorbic acid (ASA) and glutathione (GSH), which were increased by 40.24-91.22% and 9.89-17.67%, respectively, thereby reducing the oxidative stress caused by heavy metals and the contents of thiobarbituric acid-reactive substances (TBARS) and peroxidase (POD). PCR-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the effects of the tested bacteria on the cultivation-dependent and cultivation-independent bacterial communities in the root endosphere and rhizosphere soil of the rape. The sequencing results of the DGGE bands indicated that the tested bacteria colonized the endosphere and rhizosphere, and they became an important component of the cultivation-dependent bacteria. The canonical correspondence analysis (CCA) of the DGGE profile and similarity cluster analysis showed that the tested bacteria affected the cultivation-dependent and cultivation-independent bacterial communities in the root endosphere and rhizosphere. In this experiment, the effects and mechanisms of the combined plant-microbe remediation under field conditions were preliminarily studied, and the results are expected to provide a theoretical basis for future combined remediation experiments.

8.
Huan Jing Ke Xue ; 40(3): 1252-1260, 2019 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087972

RESUMO

Bacterioplankton are important components of aquatic ecosystems, and play a crucial role in the global biogeochemical cycle of nitrogen. In this study, surface-water samples were collected from Kuxin (the center of Danjiangkou Reservoir) and Qushou (the Middle Route of the South-to-North Water Diversion Project's canal head) in the Danjiangkou Reservoir in May 2016. Total DNA was isolated, and high-throughput sequencing was performed to analyze the community structure and diversity of bacteria. Phylogenetic analyses of 16S rDNA sequences showed that bacterial communities included species from 12 major phylogenetic groups. The predominant phylogenetic groups included Proteobacteria, Bacteroidetes, Firmicutes, Cyanobacteria, and Verrucomicrobia. The microbial biodiversity of Danjiangkou Reservoir bacterioplankton was greater in water samples from Qushou than in those from Kuxin. PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states) was used to determine the metabolic and functional abilities of the observed bacterial communities. Our results revealed a wide genetic diversity of organisms involved in various essential processes, such as Amino acid transport and metabolism, Transcription, Energy production and conversion, and Carbohydrate transport and metabolism. Thirty-five metabolic pathways involving nitrogen were detected. Key genes impacting the nitrogen cycle were detected in both the Kuxin and Qushou samples, and these encoded enzymes involved in nitrogen fixation (nifH), nitrification (hao), denitrification (narG、nirK、norB、nosZ), and assimilatory and dissimilatory nitrogen reduction to ammonia (nasA、narB、napA、nirA、nirB、nrfA). Copy numbers of 16S rRNA genes of each detected phylotype of Danjiangkou Reservoir bacterioplankton were uniformly higher in water samples from Kuxin than in water samples from Qushou. Our analyses of differences in nitrogen abatement potential between water samples, based on bacterial community composition and function, provide a foundation for setting water environmental protection policies in the Danjiangkou Reservoir.

9.
Antonie Van Leeuwenhoek ; 112(7): 1087-1094, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30707396

RESUMO

In this study, a Gram-negative, rod-shaped, endophytic bacterial strain (RS1T) capable of producing large amounts of exopolysaccharides was isolated from a stem of Miscanthus sinensis. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RS1T is closely related to Mucilaginibacter kameinonensis NBRC 102645T (98.72%), followed by Mucilaginibacter gossypiicola Gh-48T (97.56%) and Mucilaginibacter oryzae DSM 19975T (97.36%). The DNA G + C content of strain RS1T was determined to be 42.80 mol%. ANIb and GGDC values from genomic comparison between the genomes of strain RS1T and the related reference species were less than 95% and 70%, respectively. The major cellular fatty acids (more than 10% of total fatty acids) were identified as iso-C15: 0, C16:0, iso-C17:0-3OH and summed feature 3 (C16: 1ω7c and/or iso-C15:02-OH). The only isoprenoid quinone detected was MK-7. Based on the physiological, genotypic and genomic characteristics, strain RS1T is concluded to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter endophyticus sp. nov. is proposed (type strain RS1T = KCTC 62785T = GDMCC 1.1414T).


Assuntos
Bacteroidetes/isolamento & purificação , Endófitos/isolamento & purificação , Poaceae/microbiologia , Polissacarídeos/metabolismo , Técnicas de Tipagem Bacteriana , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/metabolismo , Composição de Bases , DNA Bacteriano/genética , Endófitos/classificação , Endófitos/genética , Endófitos/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Filogenia , Caules de Planta/microbiologia , RNA Ribossômico 16S/genética
10.
Int J Syst Evol Microbiol ; 69(4): 1149-1154, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30767848

RESUMO

A Gram-stain-negative, rod-shaped, motile bacterial strain, designated 3-5-3T, was isolated from maize-cultivated soil artificially contaminated with cadmium, in Nanyang, Henan Province, China. Strain 3-5-3T was oxidase- and catalase-positive. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 3-5-3T was affiliated with the genus Paenibacillus and most closely related to Paenibacillus anaericanus MH2T (96.5 % similarity). The average nucleotide identity and digital DNA-DNA hybridization values between 3-5-3T and the closely related species ranged 69.4-84.5 % and 18.1-18.4 %. The genomic G+C content was 53.8 mol%. Anteiso-C15 : 0 was the major fatty acid and MK-7 was the only menaquinone. The diamino acid in the cell-wall peptidoglycan contains meso-diaminopimelic acid. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, two unidentified glycolipids, two unidentified aminolipids, one unidentified phospholipid, one unidentified phosphoaminolipid and six unidentified lipids. On the basis of the results obtained in this study, strain 3-5-3T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacilluszei soli sp. nov. is proposed. The type strain is 3-5-3T (=CGMCC 1.13686T=KCTC 33998T).


Assuntos
Cádmio , Paenibacillus/classificação , Filogenia , Microbiologia do Solo , Poluentes do Solo , Zea mays , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Paenibacillus/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 69(4): 1075-1080, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30747616

RESUMO

A Gram-stain-positive, rod-shaped, motile bacterial strain, designated 3-2-2T, was isolated from field topsoil collected from a western suburb of Nanyang city, Henan province, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 3-2-2T was a member of the genus Bacillus and most closely related to Bacillus fortis R-6514T (98.9 % similarity), Bacillus terrae RA9T (98.0 %) and Bacillus fordii R-7190T (97.7 %). A draft genome sequence determined for strain 3-2-2T revealed a DNA G+C content of 42.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between 3-2-2T and the closely related Bacillus species ranged 79.4-84.2 % and 23.4-24.6 %. The major fatty acids of strain 3-2-2T were iso-C15 : 0, anteiso-C15 : 0, iso-C14 : 0 and iso-C16 : 0. The major isoprenoid quinone was MK-7. meso-Diaminopimelic acid was detected in the peptidoglycan. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and an unidentified lipid. The results of phylogenetic analyses, in silico genomic comparisons, and chemotaxonomic and phenotypic analyses clearly indicated that strain 3-2-2T represents a novel species within the genus Bacillus, for which the name Bacillus acidinfaciens sp. nov. is proposed. The type strain is 3-2-2T (=CGMCC 1.13685T=LMG 30839T).


Assuntos
Bacillus/classificação , Fazendas , Filogenia , Microbiologia do Solo , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Huan Jing Ke Xue ; 40(1): 421-429, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628301

RESUMO

Microbial communities play crucial roles in the global biogeochemical nitrogen cycle. To our knowledge, the compositions and functions of rhizosphere communities in riparian buffer strips have not been reported. In this study, rhizosphere soil samples were collected from herbs (Vetiveria zizanioides and Phragmites australis), trees (Pyrus betulifolia), and shrubs (Discocleidion rufescens) in the Danjiangkou Reservoir in June 2017. High-throughput sequencing was performed to analyze the community structure and diversity of bacteria. Phylogenetic analysis based on 16S rDNA sequences shows that the bacterial communities can be divided into 31 major phylogenetic groups. The dominant phylogenetic groups include Proteobacteria, Bacteroidetes, Actinobacteria, Gemmatimonadetes, and Acidobacteria. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) was used to determine the metabolic and functional abilities of the observed bacterial communities. Our results reveal a wide genetic diversity of organisms involved in various essential processes such as biosynthesis of other secondary metabolites, transcription, Glycan biosynthesis and metabolism, cell growth and death, and carbohydrate metabolism. Based on the 16S rRNA gene copy number of the detected phylotype, the bacterial rhizospheres of plants in riparian buffer strips can be ranked as follows:Discocleidion rufescens > Phragmites australis > Vetiveria zizanioides > Pyrus betulifolia. We analyzed the differences of different plants from the perspective of bacterial community composition and function and provide a foundation for vegetation construction and water environmental protection in riparian buffer strips of the Danjiangkou Reservoir.


Assuntos
Bactérias/classificação , Rizosfera , Microbiologia do Solo , China , Ecossistema , Filogenia , RNA Ribossômico 16S/genética
13.
Int J Syst Evol Microbiol ; 69(11): 3344-3349, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30540241

RESUMO

In a survey of endophytic bacteria in Miscanthus sinensis, a strain of Gram-negative, non-endospore-forming, rod-shaped, aerobic bacterium was isolated and designated as RS10T. Phylogenetic analysis based on its 16S rRNA gene sequence showed that the strain RS10T was affiliated with the genus Pedobacter and exhibited the highest sequence similarities to Pedobacter kyungheensis KACC 16221T (97.78 %), Pedobacter roseus KCTC 22187T (97.75 %), Pedobacter humicola KACC 18452T (97.29 %) and Pedobacter soli KACC 14939T (97.23 %). The novel strain contained iso-C15 : 0, iso-C17 : 0-3OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as major fatty acids. The only isoprenoid quinone detected in strain RS10T was MK-7. Strain RS10T contains phosphatidylethanolamine and one kind of aminophospholipid as its major polar lipids. The DNA G+C content for RS10T was 39.8 mol%. Based on the results of phenotypic and genomic characterizations, we concluded that strains RS10T represents a novel species of Pedobacter, for which the name Pedobacter miscanthi sp. nov. is proposed. The type strain is RS10T (=KCTC 62786T=GDMCC 1.1415T).


Assuntos
Pedobacter/classificação , Filogenia , Poaceae/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Pedobacter/isolamento & purificação , Fosfolipídeos/química , Caules de Planta/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
J Clin Neurosci ; 56: 114-120, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30061012

RESUMO

Metastatic spine tumour surgeries (MSTS) are indicated for preservation or restoration of neurological function, to provide mechanical stability and pain alleviation. The goal of MSTS is to improve the quality of life of the patients with spinal metastases and rarely for oncological control which is usually achieved by adjuvant therapies. Hence outcome measures such as length of stay (LOS) and rate of complications after MSTS are important indicators of quality but there is limited literature evidence for the same. We carried out a retrospective study to determine the incidence and the factors influencing normal (nLOS) and extended length of stay (eLOS) after MSTS. Data of 220 consecutive patients who underwent MSTS between 2005 and 2015 were retrieved from hospital electronic records. The preoperative, intraoperative and postoperative variables, discharge destinations as well as socioeconomic factors were analyzed. eLOS defined as positive when the LOS exceeded the 75th percentile for this cohort, was the key outcome indicator. Univariate and multivariate logistic regression analyses were performed to determine the predictive factors of eLOS. The overall median LOS was 7 days (1-30 days) and 55 patients had eLOS (LOS ≥ 11 days). Multivariate analysis revealed that significant variables independently associated with eLOS were instrumentation >9 spinal segmental levels (OR 2.89, 95% CI 1.1-7.5, p = 0.032) and presence of postoperative complications (OR 3.68, 95% CI 1.85-7.30, p < 0.001). Metastatic tumours other than breast, prostate and lung have lesser risk of eLOS (OR 0.31, 95% CI 0.14-0.70, p = 0.004). Survival estimates show that patients with eLOS have shorter survival than patients with nLOS (Crude HR 1.81, 95% CI 1.13-2.89, p = 0.003).


Assuntos
Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Neoplasias da Medula Espinal/epidemiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Alta do Paciente/estatística & dados numéricos , Neoplasias da Medula Espinal/secundário , Neoplasias da Medula Espinal/cirurgia
15.
Plant Physiol ; 178(1): 428-440, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30030326

RESUMO

The phytohormone abscisic acid (ABA) is critical for plants encountering abiotic stress. We reported previously that the Arabidopsis (Arabidopsis thaliana) transcription factor MYB30 participates in ABA responses via SUMO ligase SAP-MIZ Domain-Containing SIZ1-mediated sumoylation. Here, we show that the RING-type ubiquitin E3 ligase RHA2b, which positively regulates ABA signaling, interacted with and ubiquitinated MYB30 to modulate MYB30 stability through the 26S proteasome pathway. The degradation rate of MYB30 was repressed significantly in the rha2b-1 mutant. Phenotypic analyses showed that MYB30 acts genetically downstream of RHA2b in ABA signaling. Substitutions of lysine-283 (K283) and K165 blocked ubiquitination, suggesting that these residues are sites of ubiquitination. K283 residue substitution significantly inhibited the degradation of MYB30 induced by ABA. The K165 site functioned additively with K283 in ABA-induced MYB30 degradation and ABA responses. At the same time, sumoylation protected MYB30 from degradation under cycloheximide and ABA treatment. Compared with MYB30, overexpression of MYB30-SUMO1 partially recovered the ABA sensitivity of siz1-2 But MYB30-SUMO1 exhibited similar localization with MYB30 in nuclei. Overall, our results suggest that RHA2b targets MYB30 for degradation to modulate ABA signaling. Considering that the K283 residue also is the major site for sumoylation, we propose that sumoylation and ubiquitination act antagonistically in the ABA response to regulate the stability of MYB30 by occupying the same residue.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mutação de Sentido Incorreto , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteólise , Sumoilação/efeitos dos fármacos , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/efeitos dos fármacos
16.
Sci Rep ; 8(1): 10596, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30006549

RESUMO

Planktonic fungi are important components of aquatic ecosystems, and analyses of their community composition and function have far-reaching significance for the ecological management and maintenance of reservoir environments. However, few studies have investigated the composition, distribution, and function of planktonic fungi in reservoir ecosystems and their relationship with water quality. Here, the composition of the planktonic fungal community in the surface water layer of the Danjiangkou Reservoir is investigated using Illumina MiSeq sequencing. According to the results, the reservoir community is primarily composed of 7 phyla, including Ascomycota, Rozellomycota, Basidiomycota, Chytridiomycota, and Zygomycota, comprising 294 genera, demonstrating the rich diversity of this community. Redundancy analysis (RDA) of the planktonic fungal community and environmental factors showed dissolved oxygen (DO), chemical oxygen demand (COD), total nitrogen (TN), chlorophyll a (Chl a), and permanganate (CODMn) to be important factors influencing the distribution of planktonic fungi. Spearman correlation analysis of the planktonic fungal community composition and diversity indices with physical and chemical water quality parameters showed that the impacts of TN, COD and DO were the most significant. The results of this study on the planktonic fungal community in the Danjiangkou Reservoir area using high-throughput sequencing revealed that the community is sensitive to water quality parameters. This result provides a reference for studying the composition and distribution of the planktonic fungal community in Danjiangkou Reservoir and its role in the biogeochemical cycle.


Assuntos
Fungos/genética , Micobioma/genética , Plâncton/genética , Microbiologia da Água , Qualidade da Água , China , Fungos/isolamento & purificação , Fungos/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Plâncton/isolamento & purificação , Plâncton/metabolismo
17.
Huan Jing Ke Xue ; 39(8): 3591-3600, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998665

RESUMO

Reservoir/lake sediments are potential pollutant acceptors and sources of pollution. The Danjiangkou Reservoir, as the largest drinking water source in China, is the source water area for the Mid-route Project of the South-North Water Diversion. To illustrate the temporal and spatial changes in the environmental risks of both nutrients and heavy metals in the surface sediments of Danjiangkou Reservoir, the levels of pH, OM, TP, TN, and six kinds of metal elements during the period 2011-2016 were measured at five ecological sites. Canadian freshwater sediment quality guidelines for aquatic environments (from the CCME) were used to assess the potential ecological risks. The results showed that the contents of OM, TP, and TN in the surface sediments were 25.85, 0.57, and 1.34 g·kg-1, respectively, and those of Cr, Mn, Cu, Zn, Cd, and Pb were 57.96, 521.78, 13.91, 195.74, 0.37, and 12.92 mg·kg-1, respectively. The contents of both Zn and Cd were under the corresponding Ⅱ-level standards of soil environmental quality, but the contents of the other four heavy metals were lower than their corresponding I-level standards. After water diversion of the Mid-route Project, the OM, TN, Mn, and Zn contents increased, and the TP and other heavy metal contents displayed downward trends. Excluding the pH value, the distribution of measured nutrients and heavy metals in the surface sediments of the Danjiangkou Reservoir reached the extremely significant level (P<0.01). OM in the sediments was negatively correlated with TN and Pb, but had positive correlations with the other indicators measured. The results from the potential ecological risk assessment showed that:①Cd, Cu, and Pb had no harmful effects on organisms; ② OM had low ecological risk in most years; ③ the risk of TP was between zero and low ecological risk; and ④Cr, Zn, and TN had low ecological risk in most cases. The K and H sites had higher ecological risk for Cr, Zn, and TN, thus attention should be paid to those cases. These results illustrate the effects of human activities on nutrients and heavy metals in surface sediments.

18.
Oncotarget ; 9(37): 24801-24820, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29872507

RESUMO

Background: Tumor-associated immune cells are prognostic in non-small cell lung cancer (NSCLC) but findings have been conflicting. Objectives: To determine the prognostic role of immune cells according to localization in NSCLC patients. Methods: A systematic literature review and meta-analysis was performed on dendritic cell (DC), tumor associated macrophages (TAM), mast cells (MC), natural killer (NK) cells, T and B cells and tumor CTLA-4 and PD-L1 studies. Results: We analysed 96 articles (n= 21,752 patients). Improved outcomes were seen with increased tumor DCs (overall survival (OS) hazard ratio (HR) 0.55; 95% confidence interval (CI) 0.44-0.68), NK cells (OS HR 0.45; 0.31-0.65), TAMs (OS HR 0.33; 0.17-0.62), M1 TAMs (OS HR 0.10; 0.05-0.21), CD3+ T cells (disease specific survival (DSS) HR 0.64; 0.48-0.86), CD8+ T cells (OS HR 0.78; 0.66-0.93), B cells (OS HR 0.65; 0.42-0.99) and with increased stroma DC (DSS HR 0.62; 0.47-0.83), NK cells (DSS HR 0.51; 0.32-0.82), M1 TAMs (OS HR 0.63; 0.42-0.94), CD4+ T cells (OS HR 0.45; 0.21-0.94), CD8+ T cells (OS HR 0.77; 0.69-0.86) and B cells (OS HR 0.74;0.56-0.99). Poor outcomes were seen with stromal M2 TAMs (OS HR 1.44; 1.06-1.96) and Tregs (relapse free survival (RFS) HR 1.80; 1.34-2.43). Tumor PD-L1 was associated with worse OS (1.40; 1.20-1.69), RFS (1.67) and DFS (1.24). Conclusion: Tumor and stroma DC, NK cells, M1 TAMs, CD8+ T cells and B cells were associated with improved prognosis and tumor PD-L1, stromal M2 TAMs and Treg cells had poorer prognosis. Higher quality studies are required for confirmation.

19.
Hematol Oncol Stem Cell Ther ; 11(4): 225-232, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29705566

RESUMO

BACKGROUND: High dose Cyclophosphamide (Cy) and Vinorelbine Cyclophosphamide (Vino-Cy) are stem cell (SC) mobilisation options for patients with multiple myeloma (MM). We present a comparison of mobilisation outcomes using these regimens. PATIENTS AND METHODS: Vino-Cy patients received Vinorelbine 25 mg/m2 on day 1, cyclophosphamide 1500 mg/m2 on day 2, and pegylated GCSF on day 4 or GCSF 10 mcg/kg/day from day 4 onwards. Cy patients were given cyclophosphamide 4000 mg/m2 on day 1 and GCSF10 mcg/kg/day from day 5 onwards. The target CD34 + SC collection was 5 × 106 per kg/BW. RESULTS: 149 patients were included. SC collection was lower in the Vino-Cy group (8.20 × 106/Kg BW) compared to the Cy group (11.43 × 106/Kg BW), with adjusted geometric mean ratio of 0.59 (95% CI 0.41 to 0.86, p = 0.006). Time taken to achieve an adequate PB SC count was shorter for Vino-Cy (9 ±â€¯1 day compared to 12 ±â€¯2 days for Cy, adjusted absolute mean difference -3.95, 95% CI -4.85 to -3.06, P < .001). Mobilisation related toxicities (in particular, neutropaenic fever) were greater for Cy. CONCLUSION: Vino-Cy is a potential alternative to Cy given the need for effective mobilisation protocols with acceptable toxicity.


Assuntos
Ciclofosfamida/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Células-Tronco de Sangue Periférico , Vinorelbina/administração & dosagem , Autoenxertos , Ciclofosfamida/efeitos adversos , Feminino , Filgrastim , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Transplante de Células-Tronco de Sangue Periférico , Vinorelbina/efeitos adversos
20.
HPB (Oxford) ; 20(4): 313-320, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29100711

RESUMO

BACKGROUND: Single-staged laparoscopic common bile duct exploration (LCBDE) offers clear benefits in terms of cost and shorter hospitalization stays. However, a failed LCBDE requiring conversion to open surgery is associated with increased morbidity. This study reviewed the factors determining success of LCBDE, and created a predictive nomogram to stratify patients for the procedure. METHODS: A retrospective analysis of 109 patients who underwent LCBDE was performed. A nomogram was developed from factors significantly associated with conversion to open surgery and validated. RESULTS: Sixty-two patients underwent a successful LCBDE, while 47 patients required a conversion to open CBDE. The presence of underlying cholangitis (crude OR 2.70, 95% CI: 1.12-6.56, p = 0.017), together with its subsequent interventions, seemed to adversely increase the rate of conversion to open surgery. The predictive factors included in the nomogram for a failed laparoscopic CBDE included prior antibiotic use (adjusted OR (AOR) 2.98, 95% CI: 1.17-7.57, p = 0.022), previous ERCP (AOR 4.99, 95% CI: 2.02-12.36, p = 0.001) and abnormal biliary anatomy (AOR 9.37, 95% CI: 2.18-40.20, p = 0.003). CONCLUSION: LCBDE is useful for the treatment of choledocholithiasis. However, patients who were predicted to have an elevated risk for open conversion might not be ideal candidates for the procedure.


Assuntos
Colecistectomia Laparoscópica , Coledocolitíase/cirurgia , Técnicas de Apoio para a Decisão , Nomogramas , Adulto , Idoso , Colecistectomia Laparoscópica/efeitos adversos , Coledocolitíase/diagnóstico por imagem , Tomada de Decisão Clínica , Ducto Colédoco/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
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