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1.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2384-2392, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418242

RESUMO

A phosphate solubilizing fungus was isolated from the rhizosphere of tomato in greenhouse in Liaozhong County, Liaoning Province, Northeast China. The strain was identified as a new strain of Penicillium oxalicum by morphological characteristics and ITS rDNA sequence comparison, and then was named PSF1. Strain PSF1 could utilize various carbon sources such as glucose, sucrose, lactose, galactose, soluble starch and nitrogen sources such as ammonium sulfate, ammonium chloride, ammonium nitrate, potassium nitrate, urea for growth and metabolism, with an efficient phosphate solubilizing capacity. It grew well and had a high ability of phosphate solubilization under the conditions of C/N 10:1-60:1 and initial pH 7-8. Strain PSF1 had strong acid production ability, with the pH of culture mediums decreasing from 7.00-7.50 to 2.06-4.87 during the culture process. The highest phosphate solubilizing capacity in four phosphorus sources mediums was tricalcium phosphate (869.62 mg·L-1) > phosphate rock power (233.56 mg·L-1) > aluminum phosphate (44.77 mg·L-1) > iron phosphate (28.42 mg·L-1). Results from Pearson correlation analysis showed that there were significant negative correlations between the changes of phosphate solubili-zing capacity and pH in tricalcium phosphate, phosphate rock power and iron phosphate mediums, but no significant correlation in aluminum phosphate medium. Strain PSF1 had strong phosphate solu-bilizing capacity and wide growing conditions, thus would have strong phosphate solubilizing capacity in soil.


Assuntos
Fungos/metabolismo , Fosfatos/metabolismo , Microbiologia do Solo , China , Rizosfera , Solubilidade
2.
Ecotoxicol Environ Saf ; 182: 109449, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398778

RESUMO

The flame retardant, tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), is one of the most developmentally toxic organophosphate flame retardants (OPFRs). However, few mechanistic studies on phenotypic malformation caused by TDCIPP have been conducted. This study investigates the molecular mechanism underlying abnormal tail fin development consistently observed in zebrafish embryos exposed to TDCIPP. The results show that the defects in the tail fin (e.g., bent spine, defective caudal fin, and damaged tip) were associated with altered expression of transcription factors. The significant up-regulation of mmp9 and, among insulin-growth factor (IGF) families, igfbp-1a and igfbp1b was observed, whereas alterations in the expression of cdx4, igf1a, ifg1b, igf2b, and vegaa regulating tail development were dependent on time points. In accordance with changes in mRNA gene expression, TDCIPP impaired vessel formation and disorganized muscle in transgenic Tg(fli-GFP) zebrafish larvae. Furthermore, we found that the overexpression of mmp9 caused by TDCIPP was not linked to igfbp-1. Overall, these findings demonstrate that TDCIPP disrupts the progression of tail fin development, accompanied by defects in vessel and muscle formation in developing zebrafish embryos.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Retardadores de Chama/toxicidade , Compostos Organofosforados/toxicidade , Animais , Animais Geneticamente Modificados , Retardadores de Chama/metabolismo , Larva , Organofosfatos/metabolismo , Fosfatos/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
3.
Microbiol Res ; 227: 126309, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421713

RESUMO

The phosphorus availability in soil ranged from <0.01 to 1 ppm and found limiting for the utilization by plants. Hence, phosphate solubilizing bacteria (PSB) proficiently fulfill the phosphorus requirement of plants in an eco-friendly manner. The PSB encounter dynamic and challenging environmental conditions viz., high temperature, osmotic, acid, and climatic changes often hamper their activity and proficiency. The modern trend is shifting from isolation of the PSB to their genetic potentials and genome annotation not only for their better performance in the field trials but also to study their ability to cope up with stresses. In order to withstand environmental stress, bacteria need to restructure its metabolic network to ensure its survival. Pi starving condition response regulator (PhoB) and the mediator of stringent stress response alarmone (p)ppGpp known to regulate the global regulatory network of bacteria to provide balanced physiology under various stress condition. The current review discusses the global regulation and crosstalk of genes involved in phosphorus homeostasis, solubilization, and various stress response to fine tune the bacterial physiology. The knowledge of these network crosstalk help bacteria to respond efficiently to the challenging environmental parameters, and their physiological plasticity lead us to develop proficient long-lasting consortia for plant growth promotion.


Assuntos
Fenômenos Fisiológicos Bacterianos , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Guanosina Pentafosfato/metabolismo , Estresse Fisiológico , Bactérias/genética , Plasticidade Celular , Redes Reguladoras de Genes , Homeostase , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Nitrogênio , Fosfatos/metabolismo , Desenvolvimento Vegetal , Plantas , Solo , Estresse Fisiológico/genética
4.
Gene ; 711: 143950, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31255736

RESUMO

The marine dinoflagellate Alexandrium minutum is known to produce saxitoxins that cause paralytic shellfish poisoning in human worldwide through consumption of the contaminated shellfish mollusks. Despite numerous studies on the growth physiology and saxitoxin production of this species, the knowledge on the molecular basis of nutrient uptakes in relation to toxin production in this species is limited. In this study, relative expressions of the high-affinity transporter genes of nitrate, ammonium, and phosphate (AmNrt2, AmAmt1 and AmPiPT1) and the assimilation genes, nitrate reductase (AmNas), glutamine synthase (AmGSIII) and carbamoyl phosphate synthase (AmCPSII) from A. minutum were studied in batch clonal culture condition with two nitrogen sources (nitrate: NO3- or ammonium: NH4+) under different N:P ratios (high-P: N:P of 14 and 16, and low-P: N:P of 155). The expression of AmAmt1 was suppressed in excess NH4+-grown condition but was not observed in AmNrt2 and AmNas. Expressions of AmAmt1, AmNrt2, AmNas, AmGSIII, AmCPSII, and AmPiPT1 were high in P-deficient condition, showing that A. minutum is likely to take up nutrients for growth under P-stress condition. Conversely, relative expression of AmCPSII was incongruent with cell growth, but was well correlated with toxin quota, suggesting that the gene might involve in arginine metabolism and related toxin production pathway. The expression of AmGSIII is found coincided with higher toxin production and is believed to involve in mechanism to detoxify the cells from excess ammonium stress. The gene regulation observed in this study has provided better insights into the ecophysiology of A. minutum in relation to its adaptive strategies in unfavorable environments.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Dinoflagelados/crescimento & desenvolvimento , Proteínas de Protozoários/genética , Compostos de Amônio/metabolismo , Dinoflagelados/metabolismo , Regulação da Expressão Gênica , Nitratos/metabolismo , Fosfatos/metabolismo , Saxitoxina/genética , Estresse Fisiológico
5.
Bioresour Technol ; 291: 121854, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357041

RESUMO

Two strains, Enterobacter sp. Z1 and Klebsiella sp. Z2, were exhibited great capacities for heterotrophic nitrification-aerobic denitrification (HNAD) and intracellular phosphate accumulation. Strikingly, the co-cultured strains enhanced the removal efficiency of total nitrogen and phosphate, with removal efficiencies of ammonia, nitrate, nitrite and soluble phosphate of 99.64%, 99.85%, 96.94% and 66.7% respectively. Furthermore, high removal efficiencies from wastewaters with high concentrations of ammonia (over 1000 mg/L) were achieved by inoculation with the co-strains, which left residual ammonia of less than 1 mg/L within 10 h. To elucidate the mechanism of HNAD in co-strains, quantitative PCR was carried out to examine the expression levels of hydroxylamine oxidase (Hao), nitrate reductase (NapA and NarG), nitrite reductase (NirS) and polyphosphate kinase (Ppk), and the results showed that the napA2, narG and ppk genes in the strains were significantly upregulated under the co-cultured conditions and provided an explanation for the nitrogen and phosphate removal.


Assuntos
Enterobacter/metabolismo , Klebsiella/metabolismo , Nitrogênio/metabolismo , Fosfatos/metabolismo , Amônia/metabolismo , Desnitrificação , Processos Heterotróficos , Nitrato Redutase/metabolismo , Nitratos/metabolismo , Nitrificação , Nitrito Redutases/metabolismo , Nitritos/metabolismo , Oxirredutases/metabolismo , Águas Residuárias
6.
Bioengineered ; 10(1): 335-344, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31322471

RESUMO

Selenium-enriched yeast can transform toxic inorganic selenium into absorbable organic selenium, which is of great significance for human health and pharmaceutical industry. A yeast Rhodotorula glutinis X-20 we obtained before has good selenium-enriched ability, but its selenium content is still low for industrial application. In this study, strategies of process optimization and transport regulation of selenium were thus employed to further improve the cell growth and selenium enrichment. Through engineering phosphate transporters from Saccharomyces cerevisiae into R. glutinis X-20, the selenium content was increased by 21.1%. Through using mixed carbon culture (20 g L-1, glycerol: glucose 3:7), both biomass and selenium content were finally increased to 5.3 g L-1 and 5349.6 µg g-1 (cell dry weight, DWC), which were 1.14 folds and 6.77 folds compared to their original values, respectively. Our results indicate that high selenium-enrichment ability and biomass production can be achieved through combining process optimization and regulation of selenium transport.


Assuntos
Engenharia Metabólica/métodos , Fosfatos/metabolismo , Rhodotorula/genética , Saccharomyces cerevisiae/genética , Selênio/metabolismo , Transgenes , Transporte Biológico , Biomassa , Meios de Cultura/química , Meios de Cultura/farmacologia , Fermentação , Expressão Gênica , Glucose/química , Glucose/metabolismo , Glicerol/química , Glicerol/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Simportadores de Próton-Fosfato/genética , Simportadores de Próton-Fosfato/metabolismo , Rhodotorula/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
7.
Plant Sci ; 286: 57-67, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300142

RESUMO

Phosphorus in plant cells occurs in inorganic form as both ortho- and pyrophosphate or bound to organic compounds, like e.g., nucleotides, phosphorylated metabolites, phospholipids, phosphorylated proteins, or phytate as P storage in the vacuoles of seeds. Individual compartments of the cell are surrounded by membranes that are selective barriers to avoid uncontrolled solute exchange. A controlled exchange of phosphate or phosphorylated metabolites is accomplished by specific phosphate transporters (PHTs) and the plastidial phosphate translocator family (PTs) of the inner envelope membrane. Plastids, in particular chloroplasts, are the site of various anabolic sequences of enzyme-catalyzed reactions. Apart from their role in metabolism PHTs and PTs are presumed to be also involved in communication between organelles and plant organs. Here we will focus on the integration of phosphate transport and homeostasis in signaling processes. Recent developments in this field will be critically assessed and potential future developments discussed. In particular, the occurrence of various plastid types in one organ (i.e. the leaf) with different functions with respect to metabolism or sensing, as has been documented recently following a tissue-specific proteomics approach (Beltran et al., 2018), will shed new light on functional aspects of phosphate homeostasis.


Assuntos
Homeostase , Proteínas de Membrana Transportadoras/metabolismo , Fosfatos/metabolismo , Células Vegetais/fisiologia , Proteínas de Plantas/metabolismo , Citoplasma/fisiologia , Família Multigênica , Plastídeos/metabolismo , Transdução de Sinais
8.
Microbiol Res ; 226: 10-18, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284939

RESUMO

Microbial oxidation of antimonite [Sb(III)] to antimonate [Sb(V)] is a detoxification process which contributes to Sb(III) resistance. Antimonite oxidase AnoA is essential for Sb(III) oxidation, however, the regulation mechanism is still unknown. Recently, we found that the expressions of phosphate transporters were induced by Sb(III) using proteomics analysis in Agrobacterium tumefaciens GW4, thus, we predicted that the phosphate regulator PhoB may regulate bacterial Sb(III) oxidation and resistance. In this study, comprehensive analyses were performed and the results showed that (1) Genomic analysis revealed two phoB (named as phoB1 and phoB2) and one phoR gene in strain GW4; (2) Reporter gene assay showed that both phoB1 and phoB2 were induced in low phosphate condition (50 µM), but only phoB2 was induced by Sb(III); (3) Genes knock-out/complementation, Sb(III) oxidation and Sb(III) resistance tests showed that deletion of phoB2 significantly inhibited the expression of anoA and decreased bacterial Sb(III) oxidation efficiency and Sb(III) resistant. In contrast, deletion of phoB1 did not obviously affect anoA's expression level and Sb(III) oxidation/resistance; (4) A putative Pho motif was predicted in several A. tumefaciens strains and electrophoretic mobility shift assay (EMSA) showed that PhoB2 could bind with the promoter sequence of anoA; (5) Site-directed mutagenesis and short fragment EMSA revealed the exact DNA binding sequence for the protein-DNA interaction. These results showed that PhoB2 positively regulates Sb(III) oxidation and PhoB2 is also associated with Sb(III) resistance. Such regulation mechanism may provide a great contribution for bacterial survival in the environment with Sb and for bioremediation application.


Assuntos
Agrobacterium tumefaciens/metabolismo , Antimônio/metabolismo , Proteínas de Bactérias/metabolismo , Fosfatos/metabolismo , Agrobacterium tumefaciens/genética , Arsenitos/metabolismo , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/fisiologia , Ensaio de Desvio de Mobilidade Eletroforética , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Mutagênese Sítio-Dirigida , Oxirredução , Proteínas de Transporte de Fosfato/metabolismo , Proteômica
9.
Chemosphere ; 233: 216-222, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31173959

RESUMO

Considering the prevalence of eutrophication of water bodies, sustainable treatment technologies like constructed wetlands (CWs) have come up as a promising alternate for nutrient removal and wastewater treatment. The present study was undertaken to investigate the potential of Brachiaria-based constructed wetland for removal of phosphorus and nitrogen in different seasons of a sub-tropical region. The CW cell could efficiently remove phosphate and nitrogen under varying influent concentrations across different seasons. Average removal of total phosphate increased from 55.2% (winter) to 78.5% (spring), 80.7% (autumn), and 85.6% (summer), and maximum removal rate was 384.4 mg/m2-day during the summer season. The soluble/available phosphate was removed on priority owing to its easy bio-availability. The removal efficiency of Brachiaria increased with increasing influent phosphate concentration (5-20 mg/l), if supplemented with nitrogen maintaining the N:P ratio of 5:1. This highlighted the characteristic of Brachiaria to absorb chemical shocks w.r.t. phosphate. The neutral pH (6.2-8.3) and oxidising conditions in rhizosphere ruled out possibility of binding of phosphate with cations (Ca, Fe, and Al) in sediments. Ambient temperature and sunshine hours regulated evapotranspiration and hence nutrient removal. Simultaneous removal of nitrogen (75.6-84.6%) by Brachiaria indicated that it can serve dual purpose of nutrient removal and fodder-production for livestock, thus serving as a sustainable prototype for rural communities in sub-tropical regions.


Assuntos
Brachiaria/metabolismo , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Concentração de Íons de Hidrogênio , Índia , Nitrogênio/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Estações do Ano , Águas Residuárias , Qualidade da Água
10.
Nat Commun ; 10(1): 2829, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249296

RESUMO

Extracellular vesicles (EVs) are involved in the regulation of cell physiological activity and the reconstruction of extracellular environment. Matrix vesicles (MVs) are a type of EVs released by bone-related functional cells, and they participate in the regulation of cell mineralization. Here, we report bioinspired MVs embedded with black phosphorus (BP) and functionalized with cell-specific aptamer (denoted as Apt-bioinspired MVs) for stimulating biomineralization. The aptamer can direct bioinspired MVs to targeted cells, and the increasing concentration of inorganic phosphate originating from BP can facilitate cell biomineralization. The photothermal effect of the Apt-bioinspired MVs can also promote the biomineralization process by stimulating the upregulated expression of heat shock proteins and alkaline phosphatase. In addition, the Apt-bioinspired MVs display outstanding bone regeneration performance. Our strategy provides a method for designing bionic tools to study the mechanisms of biological processes and advance the development of medical engineering.


Assuntos
Vesículas Extracelulares/metabolismo , Fósforo/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Biomineralização , Osso e Ossos/química , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Vesículas Extracelulares/química , Feminino , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/química , Osteoblastos/metabolismo , Fosfatos/metabolismo , Fósforo/química , Ratos
11.
Artigo em Inglês | MEDLINE | ID: mdl-31192767

RESUMO

Food is an important source of human aluminium (Al) exposure and regular consumption of foods containing Al-based food additives may result in high Al intakes above health-based tolerable intakes. However, some additives are Al salts with low solubility, and little is known about bioavailability of Al in these additives. We investigated urine Al concentrations in healthy adult volunteers (N = 18, women/men) before (base-line) and after 7 days of ingestion of pancakes with a low Al content (median: <0.5 mg Al/kg) and high Al content (median: 860 mg/kg). The high-Al pancakes contained the common additive sodium aluminium phosphate (SALP). The participants did not know if the pancakes contained SALP or not during the experiment. After adjusting for creatinine content of the urine samples, median base-line Al concentrations before pancake ingestion were in the range 30-40 µmol Al/mol creatinine. Urine Al concentrations after ingestion of low-Al pancakes (average intake: <0.042 Al mg/day) did not differ significantly from the base-line levels. After ingestion of high-Al pancakes (72 mg Al/day) the median Al concentration in urine was more than 2-fold higher than at the base-line sampling before the high-Al pancake ingestion. At the end of the experiment the volunteers ingested an Al-containing antacid (Al-OH, 1800 mg Al/day) for 7 days as a positive control of Al absorption. This caused a 10-fold increase in median urine Al concentration compared to base-line. Our results strongly suggest that Al in the form of SALP in a pancake mix is bioavailable for absorption in humans, which should be taken into account in risk assessment of Al in food in countries with a high use of SALP as a food additive.


Assuntos
Compostos de Alumínio/metabolismo , Alumínio/urina , Aditivos Alimentares/metabolismo , Fosfatos/metabolismo , Compostos de Sódio/metabolismo , Adulto , Compostos de Alumínio/urina , Creatinina/urina , Feminino , Aditivos Alimentares/análise , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos/urina , Compostos de Sódio/urina
12.
Microbiol Res ; 223-225: 1-12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178042

RESUMO

Phosphorus (P) is an essential plant nutrient, but often limited in soils for plant uptake. A major economic constraint in the rice production is excessive use of chemical fertilizers to meet the P requirement. Bioaugmentation of phosphate solubilizing rhizobacteria (PSB) can be used as promising alternative. In the present study 11 mineral PSB were isolated from Basmati rice growing areas of Pakistan. In broth medium, PSB solubilized tricalcium phosphate (27-354 µg mL-1) with concomitant decrease in pH up to 3.6 due to the production of different organic acids, predominantly gluconic acid. Of these, 4 strains also have ability to mineralize phytate (245-412 µg mL-1). Principle component analysis showed that the gluconic acid producing PSB strains (Acinetobacter sp. MR5 and Pseudomonas sp. MR7) have pronounced effect on grain yield (up to 55%), plant P (up to 67%) and soil available P (up to 67%), with 20% reduced fertilization. For simultaneous validation of gluconic acid production by MR5 and MR7 through PCR, new specific primers were designed to amplify gcd, pqqE, pqqC genes responsible for glucose dehydrogenase (gcd) mediated phosphate solubilization. These findings for the first time demonstrated Acinetobacter soli as potent P solubilizer for rice and expands our knowledge about genus specific pqq and gcd primers. These two gcd containing PSB Acinetobacter sp. MR5 (DSM 106631) and Pseudomonas sp. MR7 (DSM 106634) submitted to German culture collection (DSMZ), serve as global valuable pool to significantly increase the P uptake, growth and yield of Basmati rice with decreased dependence on chemical fertilizer in P deficit agricultural soils.


Assuntos
Biofortificação , Glucose 1-Desidrogenase/genética , Oryza/crescimento & desenvolvimento , Fósforo/metabolismo , Acinetobacter/genética , Agricultura , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Proteínas de Bactérias/genética , Transporte Biológico , Meios de Cultura , Fertilizantes , Germinação , Gluconatos/metabolismo , Concentração de Íons de Hidrogênio , Paquistão , Fosfatos/metabolismo , Pseudomonas/genética , Sementes/crescimento & desenvolvimento , Solo/química , Microbiologia do Solo , Solubilidade
13.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067662

RESUMO

Potassium (K+) and phosphorous (Pi) are two of the most important nutrients required by plants and there is an interest in studying how they are acquired. Most studies have focused on the characterization of the mechanisms involved in K+ and Pi uptake and their distribution within the plants, as well as the regulatory mechanisms involved. Evidence is emerging which points to interactions in the nutrition of different nutrients and to the existence of crosstalk in the signaling cascades regulating their acquisition. However, the interaction between K+ and Pi has been scarcely studied. Here we show that high concentrations of K+ in the external solution inhibit Pi uptake and impair Pi nutrition in Arabidopsis plants, resulting in the induction of phosphate starvation response (PSR) and the upregulation of genes encoding root phosphate uptake systems. The high K+-induced PSR depends on the PHR1 and PHL1 transcription factors that are key pieces of Pi signaling in Arabidopsis. Importantly, high K+ reduces arsenic accumulation in plants and its toxic effects. The results presented may help to design strategies to reduce Pi deficiency as well as the accumulation of arsenic in crops.


Assuntos
Arabidopsis/metabolismo , Arsênico/toxicidade , Fosfatos/metabolismo , Potássio/metabolismo , Estresse Fisiológico , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte de Íons , Fosfatos/deficiência , Potássio/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Ecotoxicol Environ Saf ; 180: 130-138, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31082576

RESUMO

Open-pit mining activities for minerals and metals have left an international legacy of highly polluted soils and degraded landscapes. Reforestation is usually supposed to restore soil fertility and ecosystem services, and therefore to remediate and recover polluted sites. However, our understanding of the effects of tree species and recovery time on the restoration of abiotic and biotic soil properties remains scarce. In this study, the effects of a series of restoration chronosequence (unrestored control, 10-year, 20-year, and natural forest) and plantation types (nitrogen-fixing broad-leaved Alnus nepalensis and coniferous Cupressus torulosa monocultures, as well as their mixed plantation) on soil physicochemical and biological properties were explored in a phosphate mine. Our results showed that soil quality index (SQI), which integrates important soil physical, chemical, and biological parameters including bulk density, soil organic carbon and microbial biomass, could provide valuable information about soil health. The average SQI values of 20-year plantations were 1.55 times of 10-year plantations, and the mixed plantation was 1.13 and 1.27 times of A. nepalensis and C. torulosa monoculture, respectively. Thus, recovery time, as well as plantation type, were the main determinants of the alterations in key soil conditions during the phosphate mining restoration. At the beginning restoration (10 years), A. nepalensis monoculture performed better than C. torulosa, providing an efficient restoration strategy for early revegetation. The mixed plantation of C. torulosa and A. nepalensis showed the higher moisture and soil organic carbon than did the monocultures, especially after 20 years of revegetation. Hence, our findings address a helpful guideline for selection of tree species and plantation practices, thereby aiding in long-term success of restoration.


Assuntos
Florestas , Mineração , Fosfatos/metabolismo , Solo , Árvores/metabolismo , Biodegradação Ambiental , Ecossistema , Monitoramento Ambiental , Microbiologia do Solo , Fatores de Tempo , Árvores/classificação
15.
Arch Dis Child Fetal Neonatal Ed ; 104(5): F560-F566, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31079069

RESUMO

Metabolic bone disease of prematurity (MBDP) is characterised by skeletal demineralisation, and in severe cases it can result in fragility fractures of long bones and ribs during routine handling. MBDP arises from prenatal and postnatal factors. Infants who are born preterm are deprived of fetal mineral accumulation, 80% of which occurs in the third trimester. Postnatally, it is difficult to maintain a comparable intake of minerals, and medications, such as corticosteroids and diuretic therapy, lead to bone resorption. With improvements in neonatal care and nutrition, the incidence of MBDP in preterm infants appears to have decreased, although the recent practice of administering phosphate supplements alone will result in secondary hyperparathyroidism and associated bone loss, worsening MBDP. Postnatal immobilisation and loss of placental supply of oestrogen also contribute to skeletal demineralisation. There is no single diagnostic or screening test for MBDP, with pitfalls existing for most radiological and biochemical investigations. By reviewing the pathophysiology of calcium and phosphate homeostasis, one can establish that plasma parathyroid hormone is important in determining the aetiology of MBDP - primarily calcipaenia or phosphopaenia. This will then direct treatment with the appropriate supplements while considering optimal physiological calcium to phosphate ratios.


Assuntos
Doenças Ósseas Metabólicas , Recém-Nascido Prematuro/metabolismo , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/terapia , Cálcio/metabolismo , Gerenciamento Clínico , Humanos , Recém-Nascido , Hormônio Paratireóideo/metabolismo , Fosfatos/metabolismo
16.
J Basic Microbiol ; 59(8): 807-819, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31070248

RESUMO

A total of 45 morphologically distinct arsenic (As)-resistant bacterial strains were isolated from the soils of different regions of Chhattisgarh, India. The minimum inhibitory concentration (MIC) values of these isolates varied widely in the range of 100-500 mM for arsenate [As(V)] and 15-30 mM for arsenite [As(III)]. Out of forty-five, three isolates viz; ARP3, ARRP3, and ADT5 also revealed plant growth-promoting properties, including phosphate solubilization and production of siderophores, indoleacetic acid, ammonia, and exopolysaccharide. Besides all these, the strains not only exhibited significant growth in the presence of As(V)/As(III) but also displayed higher efficiency (87%-94%) of As removal from the growth medium followed by intracellular accumulation (17-19 mg As/g). Hydride generation atomic absorption spectroscopic (HG-AAS) analysis revealed the intracellular accumulation of As, and the structural changes that took place in these isolates were further confirmed by microscopic studies. The 16 S rRNA and phylogenetic analyses unveiled that the isolates ARP3, ARRP3, and ADT5 belonged to genera Pseudomonas, Exiguobaterium, and Microbacterium, respectively. The conducted study suggested that such beneficial bacterial strains could be conveniently exploited at a commercial level for enhancing plant growth in As-contaminated agricultural fields, thereby improved productivity and enhanced bioremediation of soil having alarming strength of As.


Assuntos
Arsenicais/metabolismo , Bactérias/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Arseniatos/metabolismo , Arseniatos/farmacologia , Arsenicais/farmacologia , Arsenitos/metabolismo , Arsenitos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Biodegradação Ambiental , Farmacorresistência Bacteriana/fisiologia , Índia , Testes de Sensibilidade Microbiana , Fosfatos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Solo/química
17.
Curr Microbiol ; 76(7): 804-809, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31025087

RESUMO

In this study, the newly designed pqq gene-specific primer sets were used for determination of phosphate-solubilizing capabilities of bacterial isolates from the agricultural regions of Erzurum. The specificity of newly designed primer sets (PqqA2F/PqqA2R, Pqq5F/Pqq5R, PqqF2/PqqF2R) were tested against ten isolates, whose phosphate-solubilizing activities were initially proved by the conventional methods. Non-phosphate-solubilizing bacteria were also chosen as negative control. According to the results, five of ten phosphate-solubilizing bacteria with PqqA2F/PqqA2R, two of ten phosphate-solubilizing bacteria with Pqq5F/Pqq5R primer set, and one of ten phosphate solubilizing with PqqF2F/PqqF2R bacteria were successfully amplificated in the PCR assay and none of the non-phosphate-solubilizing bacteria was amplificated. Then, the molecular characterization of the active phosphate-solubilizing strains was done based on the partial 16S ribosomal RNA gene region sequence analysis method. Two isolates of Enterobacter sp., 1 Rhizobium sp., 1 Enterococcus sp., 1 Bacillus cereus, 1 Bacillus atrophaeus, 1 Bacillus aryabhattai, 1 Acinetobacter sp., 1 Pseudomonas japonica, and 1 Enterobacter cloacae were identified as active phosphate-solubilizing strains. Consequently, the results showed that this specific primer sets could be used as an economic, rapid, and useful tool for the detection of phosphate-solubilizing strains in the agricultural researches.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Técnicas Bacteriológicas/métodos , Fosfatos/metabolismo , Microbiologia do Solo , Agricultura , Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Cofator PQQ/genética , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solubilidade , Turquia
18.
Contrib Nephrol ; 198: 62-72, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991406

RESUMO

BACKGROUND: Vascular calcification (VC) is common in patients with chronic kidney disease (CKD) including end-stage renal disease (ESRD). The pathogenesis of VC is complex, resulting in increased arterial stiffening, which is associated with cardiovascular mortality. In addition to traditional cardiovascular risk factors, CKD patients also have a number of non-traditional cardiovascular risk factors that may play an important role in the pathogenesis of VC. SUMMARY: Management of CKD-mineral bone disorder using conventional therapeutic approaches, which include restricting dietary phosphate, administering phosphate binders, and using active vitamin D and calcimimetics, may inhibit the progression of VC, but these approaches remain controversial because recommended biochemical targets are difficult to achieve. Current treatment strategies focus on correcting abnormal calcium, phosphate, parathyroid hormone, and vitamin D levels in ESRD patients. Novel therapies for addressing VC include magnesium and vitamin K supplementation, which are currently being investigated in randomized controlled trials. This review summarizes current treatment strategies and therapeutic targets for the management of VC in patients with ESRD. Key Messages: A better understanding of the potential therapeutic approaches to VC may lead to improved mortality rates among patients with CKD including those on dialysis. Fetuin-A inhibits VC by binding to the nanoparticles of calcium and phosphate, preventing mineral accretion. These particles are known as calciprotein particles and may provide an important pathway for mineral transport and clearance. This review article summarizes the current management of VC in patients with ESRD.


Assuntos
Falência Renal Crônica/complicações , Calcificação Vascular/tratamento farmacológico , Cálcio/metabolismo , Gerenciamento Clínico , Humanos , Fosfatos/metabolismo , Insuficiência Renal Crônica/complicações , Calcificação Vascular/etiologia , alfa-2-Glicoproteína-HS/uso terapêutico
19.
Biointerphases ; 14(2): 021005, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30966754

RESUMO

Antimicrobial surfaces such as copper alloys can reduce the spread of pathogenic microorganisms, e.g., in healthcare settings; however, the surface chemistry and thus the antibacterial activity are influenced by environmental parameters such as cleaning and disinfection procedures. Therefore, the purpose of the present study was to assess how copper-complexing compounds (chlorides and phosphates), common to the clinical environment, can affect the surface chemistry and the antiadhesive and antibacterial properties of a newly developed antibacterial copper-silver alloy and the single alloying metals. The authors demonstrated that the antiadhesion efficacy against S. aureus 8325 was the highest when the copper-silver alloy and copper surfaces (four- and two-log bacterial reduction compared to stainless steel controls, respectively) were exposed to chloride-containing suspensions. This was explained by the electrochemical activity of copper that dissolved as Cu+, highly toxic to the bacterial cells, in the presence of Cl- and eventually formed a chlorine- and oxygen-rich layer with the incorporation of phosphorus, if also phosphates were present. If chlorides were omitted from the wet environment, there was no difference (P > 0.05) in bacterial counts on copper-silver alloy, copper, silver, and AISI 316 stainless steel control surfaces, due to the fact that no oxidizing conditions were established and therefore there was no dissolution of copper ions from copper-silver alloy and copper surfaces. However, under dry conditions, copper-silver alloy and pure copper surfaces were antibacterial also in the absence of chlorides, suggesting a marked difference between dry and wet conditions in terms of the interactions between surfaces and bacteria. The authors conclude that an attentive design of control policies integrating disinfection interventions and antimicrobial surfaces, such as the copper-silver alloy coating, can be a beneficial solution in fighting the spread of antibiotic resistant bacterial strains and potentially reducing the number of disease outbreaks.


Assuntos
Ligas/farmacologia , Antibacterianos/farmacologia , Cloretos/metabolismo , Cobre/farmacologia , Fosfatos/metabolismo , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Microbiologia Ambiental , Viabilidade Microbiana/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Propriedades de Superfície
20.
Environ Pollut ; 250: 284-291, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30999205

RESUMO

Tributyl phosphate (TBP) is recognised as a global environmental contaminant because of its wide use in floatation reagents, nuclear fuel reprocessing and plasticisers. This contaminant is hardly degraded by hydrolysis in the environment due to its special physicochemical properties. In this study, one TBP-degrading strain was isolated from TBP-contaminated abandoned mine tailings, and 16S rRNA identification revealed that the strain belonged to the genus Sphingomonas. Results validated that the strain could utilise TBP as the sole carbon source, and vitamin was not the essential factor for its growth. Liquid chromatography time-of-flight mass spectrometry analysis identified di-n-butyl phosphate (DnBP) and mono-n-butyl phosphate (MnBP) as the intermediate metabolites for TBP biodegradation. No obvious change in carbon and hydrogen isotope composition was observed in biodegradation processes (cell suspension and crude extract degradation), which indicated that the first irreversible bond cleavage did not involve carbon or hydrogen. Hence, the TBP degradation scheme by Sphingomonas sp. proposed that the first irreversible step of TBP transferred to DnBP would lead to PO bond cleavage. This study combined the identification of products and isotope fractionation in substrates to investigate the transformation mechanism, thereby providing an eco-friendly and cost-effective way for the in situ bioremediation of TBP-contaminated sites by the isolated TBP degradation strain.


Assuntos
Mineração , Organofosfatos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Sphingomonas/metabolismo , Biodegradação Ambiental , Fosfatos/metabolismo , RNA Ribossômico 16S/genética , Sphingomonas/química , Sphingomonas/classificação , Sphingomonas/genética
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