Consulta: creatorFacets:"Silva-Stenico,Maria Estela"
Registros recuperados: 6
Data/hora: 13/06/2024 23:41:18

Detection of siderophores in endophytic bacteria Methylobacterium spp. associated with Xylella fastidiosa subsp. pauca
Provedor de dados: Pesquisa Agropecuária Brasileira
Autores: Lacava,Paulo Teixeira; Silva-Stenico,Maria Estela; Araújo,Welington Luiz; Simionato,Ana Valéria Colnaghi; Carrilho,Emanuel; Tsai,Siu Mui; Azevedo,João Lúcio.
The objective of this work was to study the production of siderophores by endophytic bacteria Methylobacterium spp., which occupy the same ecological niche as Xylella fastidiosa subsp. pauca (Xfp) in citrus plants. The siderophore production of Methylobacterium strains was tested according to chromeazurol agar assay test (CAS), Csáky test (hydroxamate-type) and Arnow test (catechol-type). In addition, the ability of Xfp to use siderophores, in vitro, produced by endophytic bacteria as source of iron, was evaluated. All 37 strains of Methylobacterium spp. tested were CAS-positive for siderophore production. Methylobacterium spp. produced hydroxamate-type, but not catechol-type siderophores. In vitro growth of Xfp was stimulated by the presence of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citrus variegated chlorosis; Endophytes; Heterologous siderophores; Iron; Symbionts.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2008000400011

Acúmulo de antocianinas e características físicas e químicas de frutos de laranjas sanguíneas durante o armazenamento a frio
Provedor de dados: Revista Brasileira de Fruticultura
Autores: Latado,Rodrigo Rocha; Tognato,Paola Christovam; Silva-Stenico,Maria Estela; Nascimento,Lenice Magali do; Santos,Pedro César dos.
Este trabalho teve como objetivo avaliar o conteúdo de antocianinas no suco e as características físicas e químicas dos frutos de oito variedades de laranjas sanguíneas e de laranja Valência, e, também, verificar os efeitos do armazenamento dos frutos a 10ºC, durante um período de até 60 dias, nos parâmetros avaliados. Os teores de antocianina foram determinados utilizando-se de um método espectrofotométrico, assim como dez características físicas e químicas dos frutos e dos sucos foram avaliadas antes e durante o armazenamento. Todas as variedades de laranja avaliadas apresentaram naturalmente baixos teores ou nenhum teor de antocianina no suco. O armazenamento durante um período de até 60 dias, em baixa temperatura, possibilitou acúmulo significativo de...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citrus sinensis; Antocianina; Fruto; Suco; Conservação; Frio.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452008000300007

Antifungal compound produced by the cassava endophyte Bacillus pumilus MAIIIM4a
Provedor de dados: Scientia Agricola
Autores: Melo,Flávia Mandolesi Pereira de; Fiore,Marli Fátima; Moraes,Luiz Alberto Beraldo de; Silva-Stenico,Maria Estela; Scramin,Shirlei; Teixeira,Manoel de Araújo; Melo,Itamar Soares de.
In the search for new organisms and new secondary metabolites, a study was conducted to evaluate the diversity of endophytic bacteria from ethnovarieties of cassava cultivated by Brazilian Amazon Indian tribes and also to study the secondary metabolites produced by a Bacillus pumilus strain. Sixty seven cassava endophytic bacteria were subjected to 16S rRNA sequencing and FAME analysis. The bacterial profile revealed that 25% of all endophytic isolates belonged to the genus Bacillus. The isolate B. pumilus MAIIIM4a showed a strong inhibitory activity against the fungi Rhizoctonia solani, Pythium aphanidermatum and Sclerotium rolfsii. Secondary metabolites of this strain were extracted using hexane, dichloromethane and ethyl acetate. Extracts were subjected...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ESI-MS/MS; Pumilacidin; Endophytic bacteria; Bioautography.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000500002

Degradation of textile dyes by cyanobacteria
Provedor de dados: Brazilian Journal of Microbiology
Autores: Dellamatrice,Priscila Maria; Silva-Stenico,Maria Estela; Moraes,Luiz Alberto Beraldo de; Fiore,Marli Fátima; Monteiro,Regina Teresa Rosim.
Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Dyes; Toxicity; Discoloration; Cyanobacteria; Degradation.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822017000100025

Specific amplification of iron receptor genes in Xylella fastidiosa strains from different hosts
Provedor de dados: Genetics and Molecular Biology
Autores: Pacheco,Flávia Teresa Hansen; Silva-Stenico,Maria Estela; Etchegaray,Augusto; Gomes,José Elias; Carrilho,Emanuel; Tsai,Siu Mui.
Bacterial production of siderophores may involve specific genes related to nonribosomal peptide and polyketide biosynthesis, which have not been fully identified in the genome of Xylella fastidiosa strain 9a5c. However, a search for siderophore-related genes in strain 9a5c indicated five membrane receptors, including siderophore, ferrichrome-iron and hemin receptors. All these biomolecules are thought to be associated with iron transport and utilization. Eighty isolates obtained from citrus orchards containing trees that developed citrus variegated chlorosis (CVC) were screened for siderophore production. The results demonstrated that only 10 of the isolates did not produce siderophores. Additional strains obtained from coffee, almond, mulberry, elm,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citrus variegated chlorosis; Plant pathogen; Iron-transportation; Pyoverdine; Enterobactin; Polyketide synthase; Peptide synthetase.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000100026

Identification of citrus expressed sequence tags (ESTs) encoding pleiotropic drug resistance (PDR)-like proteins
Provedor de dados: Genetics and Molecular Biology
Autores: Amaral,Alexandre Morais do; Saito,Daniel; Formighieri,Eduardo Fernandes; Rabello,Edenilson; Souza,Adriane N. de; Silva-Stenico,Maria Estela; Tsai,Siu Mui.
Pleiotropic drug resistance (PDR) proteins, a subfamily of the ATP-binding cassette (ABC) transporters, have been recently shown to play a role in plant defense against biotic and abiotic stresses. However, nothing is known about their expression in citrus. To investigate the occurrence of PDR homologues in citrus species, we have surveyed EST sequences from different tissues and conditions of the Citrus Expressed Sequence Tags (CitEST) database, through sequence similarity search analyses and inspections for characteristic PDR domains. Multiple sequence alignments, prediction of transmembrane topology and phylogenetic analysis of PDR-like proteins were additionally performed. This study allowed the identification of nine putative proteins showing...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ABC transporters; CitEST; Expressed sequence tag; Transcriptome; Stress.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500014