Abstract
This study aimed to establish the influence of protein oxidation on the ability of magnesium pyrophosphate (PP) to dissociate actomyosin. Actomyosin isolated from pork muscle then suspended in 0.1 M NaCl at pH 6.2 was oxidatively stressed with 10 μM FeCl3/0.1 mM ascorbate/1 mM H 2O2 for 6 or 12 h at 4 °C. Protein oxidation was evidenced by the loss of myosin and actin, the concomitant formation of disulphide-cross-linked polymers, and elevated myosin ATPase activity. The intrinsic viscosity of oxidized actomyosin had a weaker response to PP-Mg 2+ than that of non-oxidized actomyosin, indicating the suppression of actomyosin dissociation. Moreover, oxidized actomyosin solutions were devoid of small particles (<10 nm) and the stressed actomyosin exhibited weaker binding of PP-Mg2+ than non-oxidized, which further suggested a reduced myosin-PP interaction and subsequent dissociation of the actomyosin complexes.
Original language | English |
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Pages (from-to) | 662-668 |
Number of pages | 7 |
Journal | Food Chemistry |
Volume | 141 |
Issue number | 2 |
DOIs | |
State | Published - 2013 |
Bibliographical note
Funding Information:This research was supported by USDA AFRI Grant 2008-35503-18790 (to Y.L.X.) and an Oversea Study Fellowship from the China Scholarship Council (to Z.L.). Approved for publication as journal article number 12-07-137 by the Director of the Kentucky Agricultural Experiment Station.
Keywords
- ATPase activity
- Actomyosin dissociation
- Oxidation
- Pyrophosphate
ASJC Scopus subject areas
- Analytical Chemistry
- Food Science