Consulta: creatorFacets:"Andrade,Luciana"
Registros recuperados: 3
Data/hora: 26/07/2024 23:12:47

Bacterial production in Guanabara Bay (Rio de Janeiro, Brazil) evaluated by ³H-leucine incorporation
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Gonzalez,Alessandra M.; Paranhos,Rodolfo; Andrade,Luciana; Valentin,Jean L.
The aim of this work was to evaluate the necessary ³H-leucine concentration to estimate bacterial production in Guanabara Bay through saturation curves. A second aim was to collect preliminary data of bacterial production in two distinct sites corresponding to different water qualities: Urca inlet and Governador Island. Saturation curves were made with water samples taken at the main circulation channel of the bay, Paquetá Island, and the two sites mentioned before. The ³H-leucine curves showed similar pattern for all studied areas, indicating the ideal isotope concentration to be 10 nM. Bacterial biomass production ranged from 0.40 to 4.53 µgC L-1 h-1 in Urca and from 3.86 to 73.72 µgC L-1 h-1 in Governador Island indicating the relationship between...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Activity measurement; Heterothrophic production; Estuary; Water pollution; Eutrophication.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132000000500008

Zinc detoxification by a cyanobacterium from a metal contaminated bay in Brazil
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Andrade,Luciana; Keim,Carolina N.; Farina,Marcos; Pfeiffer,Wolfgang C.
We describe here the trapping of zinc in polyphosphate granules of the cyanobacterium Synechocystis aquatilis NPBS-3. Cells were cultured in 25 µM of zinc chloride and prepared for electron microscopy and energy-dispersive X-ray analysis. Some ultrastructural features were changed by zinc exposure, the increase of glycogen granules number being the main change. The polyphosphate granules contained phosphorus, sulphur, calcium, iron and zinc. The trapping of zinc in polyphosphate granules seemed to be an effective way of detoxifying the metal and surviving in the bay. As a non-specific mechanism, these polyphosphate granules could also be effective in trapping other metals in excess.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heavy metals; Zinc; Sepetiba Bay; Polyphosphate granules; Glycogen granules; Detoxification.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132004000100020

Distribution of HNA and LNA bacterial groups in the Southwest Atlantic Ocean
Provedor de dados: Brazilian Journal of Microbiology
Autores: Andrade,Luciana; Gonzalez,Alessandra M.; Rezende,Carlos Eduardo; Suzuki,Marina; Valentin,Jean Louis; Paranhos,Rodolfo.
Bacterioplankton was studied in a large area of Southwest Atlantic Ocean between 13 and 25ºS and 28 and 42ºW. Samples were collected in 108 stations at 20 m depth. Bacteria were enumerated by flow cytometry after nucleic acid staining with syto13 and two subgroups were differentiated: low nucleic acid content (LNA) and high nucleic acid content (HNA) bacteria. Total bacterial numbers varied from 0.37 to 5.53 10(5) cells mL-1. HNA cells represented 15 to 70% of the total number while LNA cells represented 30 to 85%. Heterotrophic bacterial production was determined by incorporation of tritiated leucine and ranged from 2.7 to 171.07 ng C L-1 h-1. No significant correlation was found between abundance and production. Nevertheless with support of multivariate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial abundance; HNA bacteria; LNA bacteria; Flow cytometry; Southwest Atlantic Ocean.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822007000200028