[摘要]:Ferritins from the liver and spleen of the cold-adapted Antarctic teleosts Trematomus bernacchii and Trematomus newnesi have been isolated and characterized. Interestingly, only H- and M-chains are expressed and no L-chains. The H-chains contain the conserved ferroxidase center residues while M-chains harbor both the ferroxidase center and the micelle nucleation site ligands. Ferritins have all organ-specific Subunit composition, they are: M homopolymers in spleen and H/M heteropolymers in liver. The M-chain homopolymer mineralizes iron at higher rate with respect to the H/M heteropolymer, which however is endowed with a lower activation energy for the iron incorporation process. indicative of a higher local flexibility. These findings and available literature data on ferritin expression in fish point to the role of tissue-specific expression of different chains in modulating the iron oxidation/mineralization process. (c) 2008 Elsevier Inc. All rights reserved.