title: Zinc to cadmium replacement in the prokaryotic zinc-finger domain.
abstract: Given the similar chemical properties of zinc and cadmium, zinc finger domains have been often proposed as mediators of the toxic and carcinogenic effects exerted by this xenobiotic metal. The effects of zinc replacement by cadmium in different eukaryotic zinc fingers have been reported. In the present work, to evaluate the effects of such substitution in the prokaryotic zinc finger, we report a detailed study of its functional and structural consequences on the Ros DNA binding domain (Ros87). We show that this protein, which bears important structural differences with respect to the eukaryotic domains, appears to structurally tolerate the zinc to cadmium substitution and the presence of cadmium does not affect the DNA binding activity of the protein. Moreover, we show for the first time how zinc to cadmium replacement can also take place in a cellular context. Our findings both complement and extend previous results obtained for different eukaryotic zinc fingers, suggesting that metal substitution in zinc fingers may be of relevance to the toxicity and/or carcinogenicity mechanisms of this metal.
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Via Vivaldi 43, 81100 Caserta, Italy. carla.isernia@unina2.it.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Malgieri
authors.forename: Maddalena
authors.initials: M
authors.lastname: Palmieri
authors.forename: Sabrina
authors.initials: S
authors.lastname: Esposito
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Maione
authors.forename: Luigi
authors.initials: L
authors.lastname: Russo
authors.forename: Ilaria
authors.initials: I
authors.lastname: Baglivo
authors.forename: Ivan
authors.initials: I
authors.lastname: de Paola
authors.forename: Danilo
authors.initials: D
authors.lastname: Milardi
authors.forename: Donatella
authors.initials: D
authors.lastname: Diana
authors.forename: Laura
authors.initials: L
authors.lastname: Zaccaro
authors.forename: Paolo Vincenzo
authors.initials: PV
authors.lastname: Pedone
authors.forename: Roberto
authors.initials: R
authors.lastname: Fattorusso
authors.forename: Carla
authors.initials: C
authors.lastname: Isernia
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D001667:Binding, Competitive; D002104:Cadmium / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008667:Metalloproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D009841:Oligonucleotides / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D015032:Zinc / Q000737:chemistry*; D016335:Zinc Fingers
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D008667:Metalloproteins; D009841:Oligonucleotides; D002104:Cadmium; D015032:Zinc