Phosphorylation of myofibrillar proteins in post-mortem ovine muscle with different tenderness.

Abstract

BACKGROUND:

Tenderness is one of the most important quality attributes especially for beef and lamb. As protein phosphorylation and dephosphorylation regulate glycolysis, muscle contraction and turnover of proteins within living cells, it may contribute to the conversion of muscle to meat. The changes of myofibrillar protein phosphorylation in post-mortem ovine muscle with different levels of tenderness were investigated in this study.

RESULTS:

The protein phosphorylation level (P/T ratio) of the tender group increased from 0.5 to 12 h post mortem and then decreased. The P/T ratio of tough group increased during 24 h post mortem, increasing faster from 0.5 to 4 h post mortem than from 4 to 24 h post mortem.The global phosphorylation level of tough meat was significantly higher than tender meat at 4, 12 and 24 h post mortem (P < 0.05). Protein identification revealed that most of the phosphoproteins were proteins with sarcomeric function; the others were involved in glycometabolism, stress response, etc. The phosphorylation levels of myofibrillar proteins, e.g. myosin light chain 2 and actin, were significantly different among groups of different tenderness and at different post-mortem time points (P < 0.05).

CONCLUSION:

Protein phosphorylation may influence meat rigor mortis through contractile machinery and glycolysis, which in turn affect meat tenderness.

• Authors: Lijuan Chen, Xin Li, Na Ni, Yue Liu, Li Chen, Zhenyu Wang, Qingwu W Shen, Dequan Zhang
• Journal: Journal of the science of food and agriculture (J Sci Food Agric) Vol. 96 Issue 5 Pg. 1474-83 (Mar 30 2016) ISSN: 1097-0010 [Electronic] England
• PMID: 25950868 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 Society of Chemical Industry.

Chemical References

• Actins
• Muscle Proteins
• Myosin Light Chains

Topics

• Actins (metabolism)
• Animals
• Cattle
• Chemical Phenomena
• Meat (analysis)
• Muscle Proteins (metabolism)
• Muscle, Skeletal (chemistry)
• Myofibrils (chemistry, ultrastructure)
• Myosin Light Chains (metabolism)
• Phosphorylation
• Postmortem Changes
• Sheep