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1.
Genes (Basel) ; 14(2)2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36833369

RESUMO

The NSAID ibuprofen (2-(4-isobutylphenyl)propanoic acid) and the structurally related 3-phenylpropanoic acid (3PPA), are widely used pharmaceutical and personal care products (PPCPs) which enter municipal waste streams but whose relatively low rates of elimination by wastewater treatment plants (WWTPs) are leading to the contamination of aquatic resources. Here, we report the isolation of three bacterial strains from a municipal WWTP, which as a consortium are capable of mineralizing ibuprofen. These were identified as the Pseudomonas citronellolis species, termed RW422, RW423 and RW424, in which the first two of these isolates were shown to contain the catabolic ipf operon responsible for the first steps of ibuprofen mineralization. These ipf genes which are associated with plasmids could, experimentally, only be transferred between other Sphingomonadaceae species, such as from the ibuprofen degrading Sphingopyxis granuli RW412 to the dioxins degrading Rhizorhabdus wittichii RW1, generating RW421, whilst a transfer from the P. citronellolis isolates to R. wittichii RW1 was not observed. RW412 and its derivative, RW421, as well as the two-species consortium RW422/RW424, can also mineralize 3PPA. We show that IpfF can convert 3PPA to 3PPA-CoA; however, the growth of RW412 with 3PPA produces a major intermediate that was identified by NMR to be cinnamic acid. This and the identification of other minor products from 3PPA allows us to propose the major pathway used by RW412 to mineralize 3PPA. Altogether, the findings in this study highlight the importance of ipf genes, horizontal gene transfer, and alternative catabolic pathways in the bacterial populations of WWTPs to eliminate ibuprofen and 3PPA.


Assuntos
Ibuprofeno , Purificação da Água , Ibuprofeno/química , Ibuprofeno/metabolismo , Anti-Inflamatórios não Esteroides , Bactérias/metabolismo , Biodegradação Ambiental
2.
mSphere ; 6(4): e0041221, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378981

RESUMO

Rhizoremediation is based on the ability of microorganisms to metabolize nutrients from plant root exudates and, thereby, to cometabolize or even mineralize toxic environmental contaminants. Novosphingobium sp. HR1a is a bacterial strain able to degrade a wide variety of polycyclic aromatic hydrocarbons (PAHs). Here, we have demonstrated that the number of CFU in microcosms vegetated with clover was almost 2 orders of magnitude higher than that in nonvegetated microcosms or microcosms vegetated with rye-grass or grass. Strain HR1a was able to eliminate 92% of the phenanthrene in the microcosms with clover after 9 days. We have studied the molecular basis of the interaction between strain HR1a and clover by phenomic, metabolomic, and transcriptomic analyses. By measuring the relative concentrations of several metabolites exudated by clover both in the presence and in the absence of the bacteria, we identified some compounds that were probably consumed in the rhizosphere; the transcriptomic analyses confirmed the expression of genes involved in the catabolism of these compounds. By using a transcriptional fusion of the green fluorescent protein (GFP) to the promoter of the gene encoding the dioxygenase involved in the degradation of PAHs, we have demonstrated that this gene is induced at higher levels in clover microcosms than in nonvegetated microcosms. Therefore, the positive interaction between clover and Novosphingobium sp. HR1a during rhizoremediation is a result of the bacterial utilization of different carbon and nitrogen sources released during seedling development and the capacity of clover exudates to induce the PAH degradation pathway. IMPORTANCE The success of an eco-friendly and cost-effective strategy for soil decontamination is conditioned by the understanding of the ecology of plant-microorganism interactions. Although many studies have been published about the bacterial metabolic capacities in the rhizosphere and about rhizoremediation of contaminants, there are fewer studies dealing with the integration of bacterial metabolic capacities in the rhizosphere during PAH bioremediation, and some aspects still remain controversial. Some authors have postulated that the presence of easily metabolizable carbon sources in root exudates might repress the expression of genes required for contaminant degradation, while others found that specific rhizosphere compounds can induce such genes. Novosphingobium sp. HR1a, which is our model organism, has two characteristics desirable in bacteria for use in remediation: its ubiquity and the capacity to degrade a wide variety of contaminants. We have demonstrated that this bacterium consumes several rhizospheric compounds without repression of the genes required for the mineralization of PAHs. In fact, some compounds even induced their expression.


Assuntos
Medicago/química , Fenantrenos/metabolismo , Raízes de Plantas/química , Sphingomonadaceae/fisiologia , Biodegradação Ambiental , Medicago/efeitos dos fármacos , Fenantrenos/análise , Fenantrenos/farmacologia , Extratos Vegetais/farmacologia , Microbiologia do Solo , Sphingomonadaceae/efeitos dos fármacos
3.
Environ Pollut ; 274: 116536, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33529903

RESUMO

The high global consumption of ibuprofen and its limited elimination by wastewater treatment plants (WWTPs), has led to the contamination of aquatic systems by this common analgesic and its metabolites. The potentially negative environmental and public health effects of this emerging contaminant have raised concerns, driving the demand for treatment technologies. The implementation of bacteria which mineralize organic contaminants in biopurification systems used to decontaminate water or directly in processes in WWTPs, is a cheap and sustainable means for complete elimination before release into the environment. In this work, an ibuprofen-mineralizing bacterial strain isolated from sediments of the River Elbe was characterized and assayed to remediate different ibuprofen-polluted media. Strain RW412, which was identified as Sphingopyxis granuli, has a 4.48 Mb genome which includes plasmid sequences which harbor the ipf genes that encode the first steps of ibuprofen mineralization. Here, we confirm that these genes encode enzymes which initiate CoA ligation to ibuprofen, followed by aromatic ring activation by a dioxygenase and retroaldol cleavage to unequivocally produce 4-isobutylcatechol and propionyl-CoA which then undergo further degradation. In liquid mineral salts medium, the strain eliminated more than 2 mM ibuprofen within 74 h with a generation time of 16 h. Upon inoculation into biopurification systems, it eliminated repeated doses of ibuprofen within a few days. Furthermore, in these systems the presence of RW412 avoided the accumulation of ibuprofen metabolites. In ibuprofen-spiked effluent from a municipal WWTP, ibuprofen removal by this strain was 7 times faster than by the indigenous microbiota. These results suggest that this strain can persist and remain active under environmentally relevant conditions, and may be a useful innovation to eliminate this emerging contaminant from urban wastewater treatment systems.


Assuntos
Sphingomonadaceae , Poluentes Químicos da Água , Purificação da Água , Descontaminação , Ibuprofeno , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 741: 140461, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32886990

RESUMO

The proliferation and possible adverse effects of emerging contaminants such as pharmaceutical and personal care products (PPCPs) in waters and the environment is a cause for increasing concern. We investigated the dissipation of three PPCPs: ibuprofen (IBP), diclofenac (DCF) and triclosan (TCS), separately and in mixtures, in the ppm range in biopurification system (BPS) microcosms, paying special attention to their effect on bacterial ecotoxicity, as well as bacterial community structure and composition. The results reveal that BPS microcosms efficiently dissipate IBP and DCF with 90% removed after 45 and 84 days of incubation, respectively. However, removal of TCS required a longer incubation period of 127 days for 90% removal. Furthermore, dissipation of the PPCPs was slower when a mixture of all three was applied to BPS microcosms. TCS had an initial negative effect on bacterial viability by a decrease of 34-43% as measured by live bacterial cell counts using LIVE/DEAD® microscopy; however, this effect was mitigated when the three PPCPs were present simultaneously. The bacterial communities in BPS microcosms were more affected by incubation time than by the PPCPs used. Nonetheless, the PPCPs differentially affected the composition and relative abundance of bacterial taxa. IBP and DCF initially increased bacterial diversity and richness, while exposure to TCS generally provoked an opposite effect without full recovery at the end of the incubation period. TCS, which negatively affected the relative abundance of Acidobacteria, Methylophilales, and Legionellales, had the largest impact on bacterial groups. Biomarker OTUs were identified in the BPS microcosms which were constrained to higher concentrations of the PPCPs and thus are likely to harbour degradation and/or detoxification mechanisms. This study reveals for the first time the effect of PPCPs on bacterial ecotoxicity and diversity in biopurification system microcosms and also facilitates the design of further applications of biomixtures to eliminate PPCPs.


Assuntos
Cosméticos , Preparações Farmacêuticas , Triclosan/análise , Poluentes Químicos da Água , Diclofenaco , Ibuprofeno
5.
Artigo em Inglês | MEDLINE | ID: mdl-30533899

RESUMO

Here, we report the genome sequences of one Achromobacter and four Pseudomonas strains isolated from sediments of the River Elbe which are highly tolerant toward the xenobiotic target compound diclofenac, a nonsteroidal anti-inflammatory drug (NSAID) and emerging contaminant.

6.
Mol Plant Microbe Interact ; 30(2): 113-126, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28027024

RESUMO

Bacteria from the Pseudomonas syringae complex belonging to phylogroups 1 and 3 (PG1 and PG3, respectively) isolated from woody hosts share a genomic region herein referred to as WHOP (from woody host and Pseudomonas spp.), which is absent in strains infecting herbaceous organs. In this work, we show that this region is also encoded in P. syringae pv. actinidifoliorum (PG1) and six additional members of PG3, namely, Pseudomonas savastanoi pv. retacarpa, three P. syringae pathovars, Pseudomonas meliae, and Pseudomonas amygdali. Partial conservation of the WHOP occurs in only a few PG2 strains. In P. savastanoi pv. savastanoi NCPPB 3335, the WHOP region is organized into four operons and three independently transcribed genes. While the antABC and catBCA operons mediate the catabolism of anthranilate and catechol, respectively, the ipoABC operon confers oxygenase activity to aromatic compounds. The deletion of antABC, catBCA, or ipoABC in NCPPB 3335 caused reduced virulence in woody olive plants without affecting knot formation in nonwoody plants; catBCA, dhoAB, and PSA3335_3206 (encoding a putative aerotaxis receptor) were also required for the full fitness of this strain exclusively in woody olive plants. Overall, this study sheds light on the evolution and adaptation of bacteria from the P. syringae complex to woody hosts and highlights the enzymatic activities encoded within the WHOP region that are essential for this process.


Assuntos
Genoma Bacteriano , Interações Hospedeiro-Patógeno/genética , Olea/microbiologia , Pseudomonas syringae/genética , Pseudomonas/patogenicidade , Madeira/microbiologia , Catecóis/metabolismo , Genes Bacterianos , Halogenação , Índigo Carmim/química , Índigo Carmim/metabolismo , Indóis/química , Indóis/metabolismo , Família Multigênica , Óperon/genética , Oxirredução , Transcrição Gênica , Virulência/genética , ortoaminobenzoatos/metabolismo
7.
Environ Sci Pollut Res Int ; 23(20): 20985-20996, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27488713

RESUMO

The aim of this study was to find polycyclic aromatic hydrocarbon (PAH)-degrading fungi adapted to polluted environments for further application in bioremediation processes. In this study, a total of 23 fungal species were isolated from a historically pyrogenic PAH-polluted soil in Spain and taxonomically identified. The dominant groups in these samples were the ones associated with fungi belonging to the Ascomycota phylum and two isolates belonging to the Mucoromycotina subphylum and Basiodiomycota phylum. We tested their ability to convert the three-ring PAH anthracene in a 42-day time course and analysed their ability to secrete extracellular oxidoreductase enzymes. Among the 23 fungal species screened, 12 were able to oxidize anthracene, leading to the formation of 9,10-anthraquinone as the main metabolite, a less toxic one than the parent compound. The complete removal of anthracene was achieved by three fungal species. In the case of Scopulariopsis brevicaulis, extracellular enzyme independent degradation of the initial 100 µM anthracene occurred, whilst in the case of the ligninolytic fungus Fomes (Basidiomycota), the same result was obtained with extracellular enzyme-dependent transformation. The yield of accumulated 9,10-anthraquinone was 80 and 91 %, respectively, and Fomes sp. could slowly deplete it from the growth medium when offered alone. These results are indicative for the effectiveness of these fungi for pollutant removal. Graphical abstract ᅟ.


Assuntos
Fungos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Fungos/isolamento & purificação , Microbiologia do Solo , Espanha , Xenobióticos/metabolismo
9.
Environ Sci Pollut Res Int ; 22(20): 15200-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25869434

RESUMO

The accident of the Prestige oil tanker in 2002 contaminated approximately 900 km of the coastline along the northern Spanish shore, as well as parts of Portugal and France coast, with a mixture of heavy crude oil consisting of polycyclic aromatic hydrocarbons, alkanes, asphaltenes and resins. The capacity of the autochthonous bacterial communities to respond to the oil spill was assessed indirectly by determining the hydrocarbon profiles of weathered oil samples collected along the shore, as well as through isotope ratios of seawater-dissolved CO2, and directly by analyses of denaturing gradient gel electrophoresis fingerprints and 16S rRNA gene libraries. Overall, the results evidenced biodegradation of crude oil components mediated by natural bacterial communities, with a bias towards lighter and less substituted compounds. The changes observed in the Proteobacteria, the most abundant phylum in marine sediments, were related to the metabolic profiles of the sediment. The presence of crude oil in the supratidal and intertidal zones increased the abundance of Alpha- and Gammaproteobacteria, dominated by the groups Sphingomonadaceae, Rhodobacteraceae and Chromatiales, whilst Gamma- and Deltaproteobacteria were more relevant in subtidal zones. The phylum Actinobacteria, and particularly the genus Rhodococcus, was a key player in the microbial response to the spill, especially in the degradation of the alkane fraction. The addition of inorganic fertilizers enhanced total biodegradation rates, suggesting that, in these environments, nutrients were insufficient to support significant growth after the huge increase in carbon sources, as evidenced in other spills. The presence of bacterial communities able to respond to a massive oil input in this area was consistent with the important history of pollution of the region by crude oil.


Assuntos
Bactérias/isolamento & purificação , Sedimentos Geológicos/microbiologia , Poluição por Petróleo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/análise , Petróleo/análise , Poluição por Petróleo/análise , RNA Bacteriano/análise , RNA Ribossômico 16S/genética , Espanha , Microbiologia da Água , Poluentes Químicos da Água/análise
12.
Endocrinol. nutr. (Ed. impr.) ; 60(10): 599-603, dic. 2013.
Artigo em Espanhol | IBECS | ID: ibc-118145

RESUMO

Objetivo Identificar fortalezas y debilidades en los protocolos españoles de atención sanitaria a personas transexuales y compararlos con los estándares internacionales actuales. Revisar el estado actual de la etiología y prevalencia de la transexualidad. Sugerir medidas para optimizar esta atención en vistas a una mejora significativa, incluyendo opciones de ahorro de recursos financieros. Métodos Comparación entre los contenidos relacionados con la transexualidad incluidos en la CIE-10, el DSM- IV y los protocolos españoles de las unidades de (trastornos de) identidad de género, los estándares internacionales para el cuidado de personas transgénero y el último borrador del DSM-5. Revisión sistemática de la literatura relacionada con la etiología y la prevalencia de la transexualidad. Resultados Se han identificado discrepancias significativas respecto al periodo mínimo de diagnóstico, el acceso a la terapia sustitutiva hormonal y el acceso a las cirugías genitales, así como a la exigencia de la experiencia de vida real. Se ha comprobado el impacto hormonal sobre la etiología de la transexualidad, y la infraestimación de su prevalencia. Se desestima la exigencia del tratamiento exclusivamente en unidades funcionales por carecer de justificación médica. Conclusiones El acceso al tratamiento endocrinológico y quirúrgico requiere una revisión profunda y se recomienda la descentralización de la atención a personas transexuales, ya que todos los hospitales universitarios disponen de psiquiatras, psicólogos clínicos y endocrinólogos. Aunque las cirugías de reasignación de género precisan además de cirujanos plásticos, su formación actual ya incluye esta especialidad (AU)


Objective To identify the strengths and weaknesses of Spanish healthcare protocols for transsexual persons and to compare them to current international protocols. To review the current status as regards transsexuality etiology and prevalence. To suggest measures to optimize care to achieve a significant improvement, including options for saving financial resources. Methods A comparison of the contents of texts related to transsexualism in the ICD-10, DSM- IV , and guidelines of the Spanish gender units with international standards of care for transgender persons and the last draft version of the DSM-5. Systematic revision of the literature related to the etiology and prevalence of transsexualism.Results Significant discrepancies have been found as regards the minimum time period for diagnosis, access to hormone replacement therapy and to genital surgery, and the requirement of the so-called real-life experience. Impact of sex hormones on the etiology of transsexualism and underestimation of its prevalence was confirmed. Conclusions The access to hormonal and surgical treatment requires a profound review, and decentralization of transsexual care is recommended, because all university hospitals haves psychiatrists, clinical psychologists, and endocrinologists available. Although gender reassignment surgery also requires plastic surgery specialists, plastic surgeons currently receive training in this field (AU)


Assuntos
Humanos , Transexualidade/epidemiologia , Qualidade da Assistência à Saúde/tendências , Administração dos Cuidados ao Paciente/organização & administração , Pessoas Transgênero/estatística & dados numéricos , Serviços de Saúde para Pessoas Transgênero/tendências , Satisfação do Paciente/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Assistência Centrada no Paciente/organização & administração
13.
Endocrinol Nutr ; 60(10): 599-603, 2013 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-23916699

RESUMO

OBJECTIVE: To identify the strengths and weaknesses of Spanish healthcare protocols for transsexual persons and to compare them to current international protocols. To review the current status as regards transsexuality etiology and prevalence. To suggest measures to optimize care to achieve a significant improvement, including options for saving financial resources. METHODS: A comparison of the contents of texts related to transsexualism in the ICD-10, DSM-IV, and guidelines of the Spanish gender units with international standards of care for transgender persons and the last draft version of the DSM-5. Systematic revision of the literature related to the etiology and prevalence of transsexualism. RESULTS: Significant discrepancies have been found as regards the minimum time period for diagnosis, access to hormone replacement therapy and to genital surgery, and the requirement of the so-called real-life experience. Impact of sex hormones on the etiology of transsexualism and underestimation of its prevalence was confirmed. CONCLUSIONS: The access to hormonal and surgical treatment requires a profound review, and decentralization of transsexual care is recommended, because all university hospitals haves psychiatrists, clinical psychologists, and endocrinologists available. Although gender reassignment surgery also requires plastic surgery specialists, plastic surgeons currently receive training in this field.


Assuntos
Transexualidade/psicologia , Transexualidade/terapia , Humanos , Classificação Internacional de Doenças , Transtornos Mentais/diagnóstico , Espanha , Transexualidade/diagnóstico
14.
Environ Pollut ; 181: 182-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23867699

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are one of the most common contaminants in soil. Arbuscular mycorrhizal (AM) fungi make host plants resistant to pollutants. This study aims to evaluate the impact of anthracene, phenanthrene and dibenzothiophene on the AM fungus Rhizophagus custos, isolated from soil contaminated by heavy metals and PAHs, under monoxenic conditions. We found a high level of tolerance in R. custos to the presence of PAHs, especially in the case of anthracene, in which no negative effect on AM-colonized root dry weight (root yield) was observed, and also a decrease in the formation of anthraquinone was detected. Increased PAH dissipation in the mycorrhizal root culture medium was observed; however, dissipation was affected by the level of concentration and the specific PAH, which lead us to a better understanding of the possible contribution of AM fungi, and in particular R. custos, to pollutant removal.


Assuntos
Glomeromycota/fisiologia , Micorrizas/fisiologia , Raízes de Plantas/microbiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise
15.
Front Microbiol ; 4: 90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23658554

RESUMO

Burkholderia xenovorans LB400, Cupriavidus necator H850, and Pseudomonas pseudoalcaligenes KF707 are bacterial strains able to mineralize biphenyl and to co-oxidize many of its halogenated derivatives (PCBs). Only strain LB400 also mineralizes a few mono- and dichlorobiphenyls, due to the presence of a functioning chlorocatechol pathway. Here, we used a Tn5-based minitransposon shuttle system to chromosomically introduce genes tcbRCDEF, encoding the chlorocatechol pathway into KF707, and genes cbdABC encoding a 2-chlorobenzoate 1,2-dioxygenase into KF707 and LB400, as well as transposon Tn4653 from the TOL plasmid, providing genes xylXYZL, encoding a broad-range toluate (methylbenzoate) dioxygenase and its dihydrodiol dehydrogenase, to extend the range for the mineralization of halogenated benzoates in LB400 and in KF707 through co-oxidation of halobenzoates into chlorocatechols. The engineered derivatives of LB400 and KF707 thus gained the ability for the mineralization of all isomeric monochloro- and bromobenzoates of the so-called lower pathway which, consequently, also allowed the mineralization of all monochlorobiphenyls and a number of di- and trichlorobiphenyls, thus preventing the accumulation of halobenzoates and of catabolites thereof. LB400 and KF707 also grow with the two commercial PCB formulations, Aroclor 1221 and Aroclor 1232, as the sole carbon and energy sources, but not with higher halogenated PCB mixtures, similar to the already published strain RW112. Repeated exposition of the modified LB400 to short pulses of UV light, over a prolonged period of time, allowed the isolation of a derivative of LB400, termed RW118, capable of growth with Aroclor 1016 still containing only traces of biphenyl, and in co-culture with modified KF707 termed RW120, and modified H850 (RW112) with Aroclor 1242, the commercial mixture already void of biphenyl and monochlorobiphenyls.

19.
Trends Biotechnol ; 29(12): 641-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21763021

RESUMO

The industrial revolution, the first agricultural 'green revolution', and the development of antibiotics and therapeutic chemicals have brought significant and undeniable benefits to the human race. However, these advances demand high levels of energy, exploit natural resources and create large amounts of waste that creates an environmental burden for our planet. The pollution rate and character of many of the pollutants results in a rapid deterioration of the environment. Bioremediation functions to isolate and select microorganisms that operate under aerobic and anoxic conditions to remove these harmful pollutants. Current 'omics' technologies allow the exploitation of the catabolic potential of microbes without the need to cultivate them. Synthetic microbiology builds new catabolic pathways to remove recalcitrant pollutants from the environment.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Pesquisa/tendências , Pesquisa Biomédica/tendências , Humanos , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética
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