title: Ferritin M of Paralichthys olivaceus possesses antimicrobial and antioxidative properties.
abstract: Ferritin is an evolutionarily conserved protein that plays a vital role in maintaining iron homeostasis. In this study, we identified a ferritin M (PoFerM) from Japanese flounder (Paralichthys olivaceus) and analyzed its biological property. PoFerM is composed of 176 amino acid residues and contains the conserved ferroxidase diiron center and the ferrihydrite nucleation center typical of M ferritins. Expression of PoFerM occurred in multiple tissues and was most abundant in blood. Bacterial infection upregulated PoFerM expression in head kidney, spleen, and liver in a time-dependent manner. Recombinant PoFerM (rPoFerM) purified from Escherichia coli exhibited iron-chelating activity and inhibited bacterial growth, whereas rPoFerMM, the mutant protein that bears alanine substitution at two conserved residues of the ferroxidase center and the ferrihydrite nucleation center, failed to do so. Oxidative protection analysis showed that rPoFerM, but not rPoFerMM, was able to alleviate the deleterious effect of H2O2-induced free radicals on plasmid DNA and primary flounder cells. Together these results indicate that PoFerM is an iron chelator with antimicrobial and antioxidative properties, all which depend on the conserved ferroxidase center and the ferrihydrite nucleation site.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, People's Republic of China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D001483:Base Sequence; D018076:DNA, Complementary; D020609:Edwardsiella tarda / Q000187:drug effects / Q000254:growth & development; D005293:Ferritins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D005432:Flounder / Q000378:metabolism*; D060226:Head Kidney / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007668:Kidney / Q000378:metabolism; D007962:Leukocytes / Q000187:drug effects; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D013154:Spleen / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D018076:DNA, Complementary; D029941:Fish Proteins; D011994:Recombinant Proteins; D005293:Ferritins; D006861:Hydrogen Peroxide