title: A novel non-heme iron-binding ferritin related to the DNA-binding proteins of the Dps family in Listeria innocua.
abstract: A multimeric protein that behaves functionally as an authentic ferritin has been isolated from the Gram-positive bacterium Listeria innocua. The purified protein has a molecular mass of about 240,000 Da and is composed of a single type of subunit (18,000 Da). L. innocua ferritin is able to oxidize and sequester about 500 iron atoms inside the protein cage. The primary structure reveals a high similarity to the DNA-binding proteins designated Dps. Among the proven ferritins, the most similar sequences are those of mammalian L chains that appear to share with L. innocua ferritin the negatively charged amino acids corresponding to the iron nucleation site. In L. innocua ferritin, an additional aspartyl residue may provide a strong complexing capacity that renders the iron oxidation and incorporation processes extremely efficient. This study provides the first experimental evidence for the existence of a non-heme bacterial ferritin that is related to Dps proteins, a finding that lends support to the recent suggestion of a common evolutionary origin of these two protein families.
authors.affiliation: Centro Biologia Molecolare, Consiglio Nazionale delle Ricerche, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Università la Sapienza, 00185 Roma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bozzi
authors.forename: G
authors.initials: G
authors.lastname: Mignogna
authors.forename: S
authors.initials: S
authors.lastname: Stefanini
authors.forename: D
authors.initials: D
authors.lastname: Barra
authors.forename: C
authors.initials: C
authors.lastname: Longhi
authors.forename: P
authors.initials: P
authors.lastname: Valenti
authors.forename: E
authors.initials: E
authors.lastname: Chiancone
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D002942:Circular Dichroism; D004268:DNA-Binding Proteins / Q000737:chemistry*; D005293:Ferritins / Q000737:chemistry*; D008087:Listeria / Q000737:chemistry*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C083911:DPS protein, Bacteria; D005293:Ferritins