@microbiologia.icb.usp.br
Biomedical Science Institute/University of São Paulo
University of São Paulo
Microbiology, Biotechnology, Molecular Biology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Cleide Barbieri de Souza and Elisabete José Vicente
EDUFU - Editora da Universidade Federal de Uberlandia
In this study E. coli recombinant clones that express the EC20 synthetic phytochelatin intracellularly were constructed. The increasement of Cd2+ biosorption capacity, and, also, the increasement of resistance to this toxic metal were analyzed. A gene that encodes the synthetic phytochelatin EC20 was synthesized in vitro. The EC20 synthetic gene was amplified by PCR, inserted into the DNA cloning vectors pBluescript®KS+ and pGEM®-TEasy, and also into the expression vectors pTE [pET-28(a)® derivative] and pGEX-T4-2®. The obtained recombinant plasmids were employed for genetic transformation of E. coli: pBsKS-EC20 and pGEM-EC20, they were introduced into DH10B and DH5α strains, similarly to pTE-EC20 and pGEX-EC20 that were introduced into BL21 strain. The EC20 expression was confirmed by SDS-PAGE analysis. The recombinant clones’ resistances to Cd2+ were determined by MIC analyses. The MIC for Cd2+ of DH10B/pBKS-EC20 and DH10B/pGEM-EC20 were 2.5 mM (EC20 induced), and 0.312 mM (EC20 repressed); respectively, 16 and 2 times higher than the control DH10B/pBsKS (0.156 mM). The MIC for Cd2+ of BL21/pTE-EC20 was 10.0 mM (EC20 induced) and 2.5 mM (EC20 repressed), compared with the control BL21/pTE which was only 1.25 mM. Analysis of ICP-AES showed that BL21/pGEX-EC20, after growth on the condition of EC20 expression, absorbed 37.5% of Cd2+, and even when cultured into the non-induction condition of EC20 expression, it absorbed 11.5%. These results allow the conclusion that recombinant E. coli clones expressing the synthetic phytochelatin EC20 show increased capacity for Cd2+ biosorption and enhanced resistance to this toxic ion.
Ronaldo Biondo, Felipe Almeida da Silva, Elisabete José Vicente, Jorge Eduardo Souza Sarkis, and Ana Clara Guerrini Schenberg
American Chemical Society (ACS)
This work describes the effects of the cell surface display of a synthetic phytochelatin in the highly metal tolerant bacterium Cupriavidus metallidurans CH34. The EC20sp synthetic phytochelatin gene was fused between the coding sequences of the signal peptide (SS) and of the autotransporter β-domain of the Neisseria gonorrhoeae IgA protease precursor (IgAβ), which successfully targeted the hybrid protein toward the C. metallidurans outer membrane. The expression of the SS-EC20sp-IgAβ gene fusion was driven by a modified version of the Bacillus subtilis mrgA promoter showing high level basal gene expression that is further enhanced by metal presence in C. metallidurans. The recombinant strain showed increased ability to immobilize Pb(2+), Zn(2+), Cu(2+), Cd(2+), Mn(2+), and Ni(2+) ions from the external medium when compared to the control strain. To ensure plasmid stability and biological containment, the MOB region of the plasmid was replaced by the E. coli hok/sok coding sequence.
Carolina Angélica Parada, Fernanda Portaro, Eliana Blini Marengo, Clécio Fernando Klitzke, Elisabete José Vicente, Marcella Faria, Osvaldo Augusto Sant’Anna, and Beatriz Lieblich Fernandes
Elsevier BV
Flávia Gomes de Góes Rocha, Fernanda B. Calvo, Karen C. Chaves, Jean P. S. Peron, Rodolfo F. Marques, Tânia R. de Borba, Marina S. Braga, Cleide B. Pereira, Elisabete J. Vicente, Roger Chammas,et al.
Wiley
Metastatic renal cell carcinoma (mRCC) is one of the most treatment‐resistant malignancies. Despite all new therapeutic advances, almost all patients develop resistance to treatment and cure is rarely seen. In the present study, we evaluated the antitumor effect of a bicistronic retrovirus vector encoding both endostatin (ES) and interleukin (IL)‐2 using an orthotopic metastatic RCC mouse model.
Gabriela Ribeiro-dos-Santos, Ronaldo Biondo, Oeber de Freitas Quadros, Elisabete José Vicente, and Ana Clara Guerrini Schenberg
Wiley
A synthetic version of the metal‐regulated gene A (mrgA) promoter from Bacillus subtilis, which in this Gram‐positive bacterium is negatively regulated by manganese, iron, cobalt, or copper turned out to promote high level of basal gene expression that is further enhanced by Co(II), Cd(II), Mn(II), Zn(II), Cu(II), or Ni(II), when cloned in the Gram‐negative bacterium Cupriavidus metallidurans. Promoter activity was monitored by expression of the reporter gene coding for the enhanced green fluorescent protein (EGFP), and cellular intensity fluorescence was quantified by flow cytometry. Expression levels in C. metallidurans driven by the heterologous promoter, here called pan, ranged from 20‐ to 53‐fold the expression level driven by the Escherichia coli lac promoter (which is constitutively expressed in C. metallidurans), whether in the absence or presence of metal ions, respectively. The pan promoter did also function in E. coli in a constitutive pattern, regardless of the presence of Mn(II) or Fe(II). In conclusion, the pan promoter proved to be a powerful tool to express heterologous proteins in Gram‐negative bacteria, especially in C. metallidurans grown upon high levels of toxic metals, with potential applications in bioremediation. Biotechnol. Bioeng. 2010;107: 469–477. © 2010 Wiley Periodicals, Inc.
F. M. Milian, A. N. Gouveia, M. R. Gual, J. O. Echeimberg, J. D. T. Arruda-Neto, F. Garcia, A. C. G. Schenberg, E. J. Vicente, O. Rodriguez, F. Guzman,et al.
Springer Science and Business Media LLC
Odanir Garcia Guerra, Ileana G.S. Rubio, Claudionor Gomes da Silva Filho, Regiane Aparecida Bertoni, Rute Cardoso dos Santos Govea, and Elisabete José Vicente
Elsevier BV
K.F. Oliveira, L. Malavolta, C.S. Souza, E.J. Vicente, and C. Laluce
Oxford University Press (OUP)
Aims: The aim of this study was to obtain improved strains of pectinolytic yeasts adapted to the conditions of an industrial fermentation process, which was continuously operated to convert citrus molasses into ethanol.
A. Deppman, J.O. Echeimberg, A.N. Gouveia, J.D.T. Arruda-Neto, F.M. Milian, N. Added, M.E. Camargo, F. Guzman, O.A.M. Helene, V.P. Likhachev,et al.
FapUNIFESP (SciELO)
We developed a model to describe the radiation-DNA interaction in water solution. The model is based on some important aspects of the Bethe Theory for the ionizing process, and on the assumption that the direct interaction between the incident particle and the DNA molecule is negligible in comparison with the indirect effect. This assumption can always be true under controlled conditions. The results show that the number of damages induced by radiation depends on the accumulated dose, on parameters related only to the medium properties, and on the DNA structure, but not on the incident particle. A few applications of the model are discussed, and results are successfully compared with experimental data. New experiments are proposed.
J.I. Dos Santos, E.J. Vicente, C.R. Paula, and W. Gambale
Springer Science and Business Media LLC
M de Andrade Rodrigues
Oxford University Press (OUP)
S.T. Casagrande, E.J. Vicente, I.M. Landgraf, and A.M.M. Kobata
FapUNIFESP (SciELO)
From 1989 to 1995, a total of 391 Haemophilus influenzae isolates were recovered from the cerebrospinal fluid (CSF) of hospitalized patients in São Paulo, Brazil. The majority of strains were isolated from infants aged less than 5 years. Strains belonging to biotype I (64.7%), biotype II (34.5%) and biotype IV (0.76%) were detected. Ninety-nine percent of these strains were serotype b. Minimal inhibitory concentration (MIC) was determined for ampicillin, chloramphenicol and ceftriaxone. The ss-lactamase assay was performed for all strains. The rate of ss-lactamase producer strains ranged from 10 to 21.4% during a period of 7 years, with an overall rate of 13.8%. Of the 391 strains analyzed, none was ss-lactamase negative ampicillin resistant (BLNAR). A total of 9.7% of strains showed resistance to both ampicillin and chloramphenicol; however, 4% of them were resistant to ampicillin only and 2% to chloramphenicol. All strains were susceptible to ceftriaxone and the MIC90 was 0.007 microg/ml, suggesting that ceftriaxone could be an option for the treatment of bacterial meningitis in pediatric patients who have not been screened for drug sensitivity.
Marcos Antonio de Morais, Elisabete José Vicente, Jela Brozmanova, Ana Clara Guerrini Schenberg, and João Antonio Pegas Henriques
Springer Science and Business Media LLC
João Renato Rebello Pinho, Philip J. Barr, Elizabete José Vicente, and Ana Clara Schenberg
Springer Science and Business Media LLC
Santuza Maria Ribeiro Teixeira, Ana Clara Schenberg Frascino, Elisabete Vicente Galembeck, Maristela de Oliveira Azevedo, and Spartaco Astolfi Filho
Elsevier BV