Protein extracts and aggregates forming in minced cod (Gadus morhua) during frozen storage
Natural actomyosin was extracted from frozen minced cod muscle stored for up to 62 weeks at -20 °C with 0.6 M NaCl, and the insoluble aggregates, when formed, were solubilized successively with 2% sodium dodecyl sulfate (SDS) and 2% SDS + 5% β-mercaptoethanol (ME) solutions, giving extracted fractio...
Published in: | Journal of Agricultural and Food Chemistry |
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Main Authors: | , , , , , , |
Other Authors: | |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
American Chemical Society
1996
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Subjects: | |
Online Access: | http://hdl.handle.net/10261/94617 https://doi.org/10.1021/jf960158w https://doi.org/10.13039/501100000780 |
Summary: | Natural actomyosin was extracted from frozen minced cod muscle stored for up to 62 weeks at -20 °C with 0.6 M NaCl, and the insoluble aggregates, when formed, were solubilized successively with 2% sodium dodecyl sulfate (SDS) and 2% SDS + 5% β-mercaptoethanol (ME) solutions, giving extracted fractions S1 (NaCl), S2 (SDS), and S3 (ME + SDS), precipitates insoluble in 0.6 M NaCl (P1) and 2% SDS (P2), and a precipitate not soluble in any of the agents used (P3). SDS polyacrylamide gel electrophoresis (SDS-PAGE) of fraction S1 showed that the proportion of the major proteins changed during frozen storage. Size exclusion chromatography snowed a decrease in the peak containing myosin heavy chain (MHC) and actin (Ac). Transmission electron microscopy (TEM) of S1 showed at the outset a filamentous morphology associated with globules interconnected crosswise. As storage progressed, the number and size of aggregates increased. In fractions S2 and S3, the major proteins detected by SDS-PAGE were MHC and Ac. TEM showed a greater abundance of ring-shaped structures than in S1. TEM of the insoluble fractions showed a sarcomerelike structure, more pronounced the milder the solubilizing treatment and the longer the storage time. This work is part of a project financed by the EU (Project FAR-UP3 647),Spanish ALI 92-1354-CE and ALI 94-0954-CO2-01-02. Peer Reviewed |
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