title: Microbial interactions with chromium: basic biological processes and applications in environmental biotechnology.
abstract: Chromium (Cr) is a highly toxic metal for microorganisms as well as plants and animal cells. Due to its widespread industrial use, Cr has become a serious pollutant in diverse environmental settings. The hexavalent form of the metal, Cr(VI), is considered a more toxic species than the relatively innocuous and less mobile Cr(III) form. The study of the interactions between microorganisms and Cr has been helpful to unravel the mechanisms allowing organisms to survive in the presence of high concentrations of Cr(VI) and to detoxify and remove the oxyanion. Various mechanisms of interactions with Cr have been identified in diverse species of bacteria and fungi, including biosorption, bioaccumulation, reduction of Cr(VI) to Cr(III), and chromate efflux. Some of these systems have been proposed as potential biotechnological tools for the bioremediation of Cr pollution using bioreactors or by in situ treatments. In this review, the interactions of microorganisms with Cr are summarised, emphasising the importance of new research avenues using advanced methodologies, including proteomic, transcriptomic, and metabolomic analyses, as well as the use of techniques based on X-ray absorption spectroscopy and electron paramagnetic resonance spectroscopy.
authors.affiliation: Departamento de Biología, DCNE, Universidad de Guanajuato, 36050, Guanajuato, GTO, Mexico. xilefgu@gmail.com.
authors.forename: J F
authors.initials: JF
authors.lastname: Gutiérrez-Corona
authors.affiliation: Departamento de Biología, DCNE, Universidad de Guanajuato, 36050, Guanajuato, GTO, Mexico.
authors.forename: P
authors.initials: P
authors.lastname: Romo-Rodríguez
authors.affiliation: Departamento de Biología, DCNE, Universidad de Guanajuato, 36050, Guanajuato, GTO, Mexico.
authors.forename: F
authors.initials: F
authors.lastname: Santos-Escobar
authors.affiliation: Laboratorio de Neurobiología Molecular y Celular, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus UNAM Juriquilla, 76230, Querétaro, QRO, Mexico.
authors.forename: A E
authors.initials: AE
authors.lastname: Espino-Saldaña
authors.affiliation: Departamento de Ingeniería Química, DCNE, Universidad de Guanajuato, 36050, Guanajuato, GTO, Mexico.
authors.forename: H
authors.initials: H
authors.lastname: Hernández-Escoto
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D001673:Biodegradation, Environmental; D002857:Chromium / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004785:Environmental Pollutants / Q000378:metabolism*; D005658:Fungi / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D020869:Gene Expression Profiling; D055432:Metabolomics; D040901:Proteomics; D056928:X-Ray Absorption Spectroscopy
chemical_list: D004785:Environmental Pollutants; D002857:Chromium
keywords: Bioremediation; Chromium contamination; Microbial Cr(VI) reduction and absorption