IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
artículos
Título:
Dissecting the Metal Selectivity of MerR Monovalent Metal Ion Sensors in Salmonella
Autor/es:
IBÁÑEZ, MARÍA M.; CERMINATI, SEBASTIÁN; CHECA, SUSANA K.; SONCINI, FERNANDO C.
Revista:
JOURNAL OF BACTERIOLOGY
Editorial:
AMER SOC MICROBIOLOGY
Referencias:
Lugar: Washington; Año: 2013 vol. 195 p. 3084 - 3092
ISSN:
0021-9193
Resumen:
Two homologous transcription factors, CueR and GolS, that belong to the
MerR metalloregulatory family are responsible for Salmonella Cu and Au
sensing and resistance, respectively. They share similarities not only
in their sequences, but also in their target transcription binding
sites. While CueR responds similarly to Au, Ag, or Cu to induce the
expression of its target genes, GolS shows higher activation by Au than
by Ag or Cu. We showed that the ability of GolS to distinguish Au from
Cu resides in the metal-binding loop motif. Here, we identify the amino
acids within the motif that determine in vivo metal selectivity. We show
that residues at positions 113 and 118 within the metal-binding loop
are the main contributors to metal selectivity. The presence of a Pro
residue at position 113 favors the detection of Cu, while the presence
of Pro at position 118 disfavors it. Our results highlight the molecular
bases that allow these regulators to coordinate the correct metal ion
directing the response to a particular metal injury.