title: Oxidation of myofibrillar proteins and impaired functionality: underlying mechanisms of the carbonylation pathway.
abstract: The potential impact of protein oxidation on the functional properties of myofibrillar proteins (MP) was investigated in the present study. To accomplish this purpose, myofibrillar proteins were oxidized in vitro for 12 days at 37 °C in the presence of Cu(2+), Fe(3+), and Mb in combination with H(2)O(2) and analyzed at sampling times for chemical changes induced by oxidative reactions and functional properties. The oxidation measurements included specific protein carbonyls (α-aminoadipic semialdehyde, AAS), advanced lysine oxidation products (α-aminoadipic acid, AAA, and Schiff bases), and thiobarbituric acid-reactive substances (TBARS). The factors and mechanisms involved in the oxidative degradation of lysine residues through the carbonylation pathway are precisely described. According to the present results, intense lipid and protein carbonylation, principally induced by Cu(2+)/systems, leads to a fast and severe loss of MP functionality, including impaired water-holding, foaming, and gelling capacities. The implication of Mb in the oxidation events enhances the production of AAA and Schiff bases, compromising to a larger extent the solubility of MP and worsening the aggregation and the gelling capacity. The connection between the oxidation-induced chemical changes and the loss of protein functionality is thoroughly discussed.
authors: Department of Animal Production and Food Science, Food Technology, University of Extremadura, 10003 Cáceres, Spain.
authors: Mariana
authors: M
authors: Utrera
authors: Mario
authors: M
authors: Estévez
mesh_terms: D003300:Copper / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D008239:Lysine / Q000737:chemistry; D008982:Molybdenum / Q000737:chemistry; D009124:Muscle Proteins / Q000737:chemistry* / Q000502:physiology*; D009210:Myofibrils / Q000737:chemistry*; D010084:Oxidation-Reduction; D050050:Protein Carbonylation; D013329:Structure-Activity Relationship
chemical_list: D005290:Ferric Compounds; D009124:Muscle Proteins; D003300:Copper; D008982:Molybdenum; D006861:Hydrogen Peroxide; D008239:Lysine