Changes in glycolytic and mitochondrial protein profiles regulates postmortem muscle acidification and oxygen consumption in dark-cutting beef

Dark-cutting beef is a condition in which fails to have characteristic bright-red color when the cut surface exposed oxygen. However, mechanistic basis for this occurrence not clear. Protein expression profiles were compared between dark-cutting and normal-pH using LC-MS/MS-based proteomics. Mass spectrometry analysis identified 1162 proteins proteomes of beef. Of these, 92 had significant changes protein abundance versus In beef, 25 down-regulated, including enzymes related glycogen metabolism, glucose homeostasis, denovo synthesis adenosine monophosphate (AMP), phosphorylase activity. comparison, 27 up-regulated oxidation-reduction processes, muscle contraction, oxidative phosphorylation. Down-regulation glycogenolytic suggests decreased mobilization utilization, while up-regulation mitochondrial transport chain indicates greater capacity support respiration These results showed that involved glycogenolysis electron would promote development high-pH oxygen consumption, respectively; thus limiting myoglobin oxygenation The current understanding defective glycolysis causes less carbon flow, leading postmortem lactic acid formation elevated pH best our knowledge, limited research has evaluated how glycolytic regulate acidification consumption We utilized shotgun proteomics approach elucidate potential differences may influence metabolism characteristics. Our study shows down-regulation glycolgenolytic IMP/AMP biosynthetic addition, content coupled with higher are conducive factors enhanced oxygenation, contributing dark meat typically associated