| Autor: |
Rodríguez-Sánchez V; Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas 'Francisco García Salinas', Avenida Preparatoria S/n, Col. Agronómica II, 98066, Zacatecas, ZAC., Mexico., Guzmán-Moreno J; División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica A. C., Camino A la Presa de San José 2055, Lomas 4 Seccion, 78216, San Luis, S.L.P., Mexico., Rodríguez-González V; División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica A. C., Camino a la Presa de San José 2055, Lomas 4 seccion, 78216, San Luis, S.L.P., Mexico., Flores-de la Torre JA; Unidad Académica de Ciencias Químicas, Universidad Autónoma de Zacatecas 'Francisco García Salinas', Campus UAZ siglo XXI. 2, Carr. a Guadalajara Km 6, Ejido La Escondida, 98160, Zacatecas, ZAC., Mexico., Ramírez-Santoyo RM; Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas 'Francisco García Salinas', Avenida Preparatoria S/n, Col. Agronómica II, 98066, Zacatecas, ZAC., Mexico., Vidales-Rodríguez LE; Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas 'Francisco García Salinas', Avenida Preparatoria S/n, Col. Agronómica II, 98066, Zacatecas, ZAC., Mexico. luzelenavr@uaz.edu.mx. |
| Abstrakt: |
The study of metal-tolerant bacteria is important for bioremediation of contaminated environments and development of green technologies for material synthesis due to their potential to transform toxic metal ions into less toxic compounds by mechanisms such as reduction, oxidation and/or sequestration. In this study, we report the isolation of seven lead-tolerant bacteria from a metal-contaminated site at Zacatecas, México. The bacteria were identified as members of the Staphylococcus and Bacillus genera by microscopic, biochemical and 16S rDNA analyses. Minimal inhibitory concentration of these isolates was established between 4.5 and 7.0 mM of Pb(NO 3 ) 2 in solid and 1.0-4.0 mM of Pb(NO 3 ) 2 in liquid media. A quantitative analysis of the lead associated to bacterial biomass in growing cultures, revealed that the percentage of lead associated to biomass was between 1 and 37% in the PbT isolates. A mechanism of complexation/biosorption of lead ions as inorganic phosphates (lead hydroxyapatite and pyromorphite) in bacterial biomass, was determined by Fourier transform infrared spectroscopy and X-ray diffraction analyses. Thus, the ability of the lead-tolerant isolates to transform lead ions into stable and highly insoluble lead minerals make them potentially useful for immobilization of lead in mining waste. |
Full text from SpringerLink