INVESTIGADORES
CHECA Susana Karina
artículos
Título:
Bacterial gold sensing and resistance
Autor/es:
CHECA, S. K. (CORR. AUTHOR); SONCINI, F. C. (CORR. AUTHOR)
Revista:
BIOMETALS
Editorial:
SPRINGER
Referencias:
Lugar: New York; Año: 2011 vol. 24 p. 419 - 427
ISSN:
0966-0844
Resumen:
IMPORTANTE: CHECA SK Y SONCINI FC SON AUTORES DE CORRESPONDENCIA EN ESTA PUBLICACIÓN. Calification SCImago-Q1, IF (2011) 2.823. Gold ions are mobilized anddisseminated through the environment and enter into the cells by non-specific intake. To avoid deleterious effect that occurs even at very low concentrations, bacteria such as Salmonella enterica and Cupriavidus metallidurans use Au-specific MerR-type transcriptional regulators to detect the presence of these toxic ions, and control the expression of specific resistance factors. In contrast to the related copper sensor CueR, the Au-selective metalloregulatory proteins are able to distinguish Au(I) from Cu(I) or Ag(I). This is achieved by finely tuning a single dithiolate metal coordination with conserved cysteine residues at the metal binding site of the proteins to lower the affinity for Cu(I) in comparison to the Cu-sensors, while maintaining or even increasing the affinity for Au(I). In Salmonella , GolS not only privileges the binding of Au(I) over Cu(I) or Ag(I), but also distinguishes its target recognition sites in its regulated promoters minimizing cross-activation of CueR-controlled operators. In this sense, the presence of a selective Au sensory devise would allow species harbouring resident Cu-homeostasis systems to eliminate the toxic ion without affecting Cu acquisition in Au rich environments.