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1.
Microb Ecol ; 81(1): 267-277, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32681284

RESUMEN

Pigmented bacterial symbionts play major roles in the health of coral holobionts. However, there is scarce knowledge on the diversity of these microbes for several coral species. To gain further insights into holobiont health, pigmented bacterial isolates of Fabibacter pacificus (Bacteroidetes; n = 4), Paracoccus marcusii (Alphaproteobacteria; n = 1), and Pseudoalteromonas shioyasakiensis (Gammaproteobacteria; n = 1) were obtained from the corals Mussismilia braziliensis and Montastraea cavernosa in Abrolhos Bank, Brazil. Cultures of these bacterial symbionts produced strong antioxidant activity (catalase, peroxidase, and oxidase). To explore these bacterial isolates further, we identified their major pigments by HPLC and mass spectrometry. The six phylogenetically diverse symbionts had similar pigment patterns and produced myxol and keto-carotene. In addition, similar carotenoid gene clusters were confirmed in the whole genome sequences of these symbionts, which reinforce their antioxidant potential. This study highlights the possible roles of bacterial symbionts in Montastraea and Mussismilia holobionts.


Asunto(s)
Antozoos/microbiología , Antioxidantes/metabolismo , Bacteroidetes/metabolismo , Paracoccus/metabolismo , Pigmentos Biológicos/metabolismo , Pseudoalteromonas/metabolismo , Animales , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Brasil , Carotenoides/metabolismo , Catalasa/biosíntesis , ADN Bacteriano/genética , Genoma Bacteriano/genética , Oxidorreductasas/biosíntesis , Paracoccus/genética , Paracoccus/aislamiento & purificación , Peroxidasa/biosíntesis , Pigmentos Biológicos/genética , Pseudoalteromonas/genética , Pseudoalteromonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Simbiosis
2.
Int J Syst Evol Microbiol ; 69(9): 2794-2800, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31310192

RESUMEN

An orange-pigmented, oxidase-positive bacterial strain (I-41R45T), isolated from the kidney of a black rock cod fish sampled in the Chilean Antarctic was studied in a polyphasic taxonomic investigation. Cells of the isolate were coccoid and stained Gram-negative. A comparison of the 16S rRNA gene sequence of strain I-41R45T with sequences of type strains of most closely related Paracoccus species showed highest sequence similarities to Paracoccus hibiscisoli (98.4 %), Paracoccus marcusii (98.3 %), Paracoccus haeundaensis and Paracoccus carotinifaciens (both 98.2 %). 16S rRNA gene sequence similarities to all other Paracoccus species were below 97 %. The draft genome of strain I-41R45T had a size of 4.59 Mb with a DNA G+C content of 65.26 mol% and included the prediction and annotation of 4426 coding genes, 1973 protein-coding genes and 46 tRNAs. The fatty acid profile of strain I-41R45T consisted mainly of the major fatty acids C18 : 1 ω7c/ω9t/ω12t and C18:0, typical of the genus Paracoccus. DNA-DNA hybridizations between I-41R45T and type strains of P. hibiscisoli, P. marcusiiand P. haeundaensis resulted in similarity values of 45 % (reciprocal 26 %), 66 % (reciprocal 61 %), and 29 % (reciprocal 36 %), respectively. DNA-DNA hybridization results, together with the differentiating biochemical and chemotaxonomic properties, showed that strain I-41R45T represents a novel Paracoccus species, for which the name Paracoccus nototheniae sp. nov. (type strain I-41R45T=CCM 8875T=CIP 111632T), is proposed.


Asunto(s)
Riñón/microbiología , Paracoccus/clasificación , Perciformes/microbiología , Filogenia , Animales , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , Chile , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Paracoccus/aislamiento & purificación , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
3.
Electron. j. biotechnol ; Electron. j. biotechnol;31: 10-16, Jan. 2018. graf, tab, ilust
Artículo en Inglés | LILACS | ID: biblio-1022030

RESUMEN

Background: Biodegradation is a reliable approach for efficiently eliminating persistent pollutants such as chlorpyrifos. Despite many bacteria or fungi isolated from contaminated environment and capable of degrading chlorpyrifos, limited enzymes responsible for its degradation have been identified, let alone the catalytic mechanism of the enzymes. Results: In present study, the gene cpd encoding a chlorpyrifos hydrolase was cloned by analysis of genomic sequence of Paracoccus sp. TRP. Phylogenetic analysis and BLAST indicated that CPD was a novel member of organophosphate hydrolases. The purified CPD enzyme, with conserved catalytic triad (Ser155-Asp251-His281) and motif Gly-Asp-Ser-Ala-Gly, was significantly inhibited by PMSF, a serine modifier. Molecular docking between CPD and chlorpyrifos showed that Ser155 was adjacent to chlorpyrifos, which indicated that Ser155 may be the active amino acid involved in chlorpyrifos degradation. This speculation was confirmed by site-directed mutagenesis of Ser155Ala accounting for the decreased activity of CPD towards chlorpyrifos. According to the key role of Ser155 in chlorpyrifos degradation and molecular docking conformation, the nucleophilic catalytic mechanism for chlorpyrifos degradation by CPD was proposed. Conclusion: The novel enzyme CPD was capable of hydrolyze chlorpyrifos and Ser155 played key role during degradation of chlorpyrifos.


Asunto(s)
Paracoccus/enzimología , Cloropirifos/metabolismo , Esterasas/metabolismo , Organofosfatos/metabolismo , Biodegradación Ambiental , Catálisis , Mutagénesis , Clonación Molecular , Análisis de Secuencia , Esterasas/aislamiento & purificación , Esterasas/genética , Hidrólisis , Metales/metabolismo
4.
Curr Genet ; 63(3): 509-518, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27796486

RESUMEN

One of the main goals of coral microbiology is to understand the ways in which coral-bacteria associations are established and maintained. This work describes the sequencing of the genome of Paracoccus sp. SM22M-07 isolated from the mucus of the endemic Brazilian coral species Mussismilia hispida. Comparative analysis was used to identify unique genomic features of SM22M-07 that might be involved in its adaptation to the marine ecosystem and the nutrient-rich environment provided by coral mucus, as well as in the establishment and strengthening of the interaction with the host. These features included genes related to the type IV protein secretion system, erythritol catabolism, and succinoglycan biosynthesis. We experimentally confirmed the production of succinoglycan by Paracoccus sp. SM22M-07 and we hypothesize that it may be involved in the association of the bacterium with coral surfaces.


Asunto(s)
Antozoos/genética , Genoma Bacteriano , Paracoccus/genética , Simbiosis/genética , Animales , Antozoos/crecimiento & desarrollo , Antozoos/microbiología , Brasil , ADN Bacteriano/genética , Ecosistema , Paracoccus/crecimiento & desarrollo , Filogenia
5.
Neotrop Entomol ; 45(6): 692-697, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27389187

RESUMEN

The worldwide mealybug genus Paracoccus Ezzat & McConnell (Hemiptera: Coccomorpha: Pseudococcidae) has eight described Neotropical species, including two species known from Brazil. In this article, we describe a third species from Brazil: Paracoccus galzerae Pacheco da Silva & Kaydan sp. n., based on the morphology of adult females collected on the roots of Conyza bonariensis (Asteraceae) in vineyards in Bento Gonçalves City, Rio Grande do Sul. A revised identification key including the new species is provided for the Neotropical region.


Asunto(s)
Hemípteros/clasificación , Animales , Asteraceae , Brasil , Femenino , Paracoccus
6.
Rio de Janeiro; VideoSaúde; 2014. 23m.
No convencional en Portugués | LILACS | ID: lil-756817

RESUMEN

O Congresso aconteceu na UERJ, e fala sobre a mobilização social; a luta pela democratização da comunicação; a Comissão da Verdade da Reforma Sanitária; resultados da indução ao consumo, entre outros temas. O presidente da Abrasco considera este Congresso um produtor de subsídios para melhoria das políticas de saúde e das práticas dos serviços de saúde. entrevistados: Kenneth Rochel Camargo Junior, Roseni Pinheiro, Luis Eugenio de Souza, Madel Luz, Carine Abreu, Laura da Maia, Sharlene Goulart, Maria Salete Bessa Jorge, Mardenia Gomes, Ana Maria Tambellini, Modesto da Silveira, Umberto Trigueiros, Jean Wyllys, Janine Cardoso, Aurea Pitta, Orlando Guilhon, Rogério Lannes, Paulo Vaz, Paula Sibilia, Beto Novaes, Carlos Minayo, Ziadir Francisco Coutinho, Eduardo Thielen...


Asunto(s)
Humanos , Adolescente , Comunicación en Salud , Accesibilidad a los Servicios de Salud , Derechos Humanos , Participación de la Comunidad , Salud Rural , Discriminación Social , Aislamiento Social , Sistema Único de Salud/tendencias , Democracia , Paracoccus , Plaguicidas , Comercialización de Medicamentos , Red Social , Suicidio
7.
J Hazard Mater ; 139(2): 301-9, 2007 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-16872740

RESUMEN

A horizontal-flow anaerobic immobilized biomass reactor (HAIB) containing denitrifying biomass was evaluated with respect to its ability to remove, separately and in a short operating period (30 days), organic matter, nitrate, and the hydrocarbons benzene (41.4 mg L-1), toluene (27.8 mg L-1), ethylbenzene (31.1 mg L-1), o-xylene (28.5 mg L-1), m-xylene (28.4 mg L-1) and p-xylene (32.1 mg L-1). The purified culture, which was grown in the presence of the specific hydrocarbon, was used as the source of cells to be immobilized in the polyurethane foam. After 30 days of operation, the foam was removed and a new immobilized biomass was grown in the presence of another hydrocarbon. The average hydrocarbon removal efficiency attained was 97%. The organic matter, especially ethanol, was removed with an average efficiency of 83% at a mean influent concentration of 1185.0 mg L-1. A concomitant removal of 97% of nitrate was observed for a mean influent concentration of 423.4 mg L-1. The independent removal of each hydrocarbon demonstrated that these contaminants can be biodegraded separately, without the need for a compound to be the primary substrate for the degradation of another. This study proposes the application of the system for treatment of areas contaminated with these compounds, with substitution and formation of a biofilm in a 30-day period.


Asunto(s)
Reactores Biológicos/microbiología , Etanol/metabolismo , Hidrocarburos Aromáticos/metabolismo , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Anaerobiosis , Biodegradación Ambiental , Células Inmovilizadas/metabolismo , Paracoccus/crecimiento & desarrollo , Paracoccus/aislamiento & purificación , Paracoccus/ultraestructura , Pseudomonas/crecimiento & desarrollo , Pseudomonas/aislamiento & purificación , Pseudomonas/ultraestructura
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