Supranutritional Supplementation of Vitamin E Influences Myoglobin Post-Translational Modifications in Postmortem Beef Longissimus Lumborum Muscle

Post-translational modifications (PTM) in myoglobin (Mb) can influence fresh meat color stability. Dietary supplementation of vitamin E improves beef stability by delaying lipid oxidation–induced Mb oxidation and influences proteome profile postmortem skeletal muscles. Nonetheless, the on PTM muscles has yet to be investigated. Therefore, objective current study was examine effect dietary longissimus lumborum muscle. Beef muscle samples (24 h postmortem) were obtained from carcasses 9 E–supplemented (VITE; 1,000 IU diet/heifer·d−1for 89 d) control (CONT; no supplemental E) heifers. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis used separate other sarcoplasmic proteins Tandem mass spectrometry identified multiple (phosphorylation, acetylation, 4-hydroxynonenalalkylation, methylation, dimethylation, trimethylation, carboxymethylation) protein bands (17 kDa) representing Mb. The amino acids susceptible phosphorylation threonine (T) tyrosine (Y), whereas lysine (K) residues prone PTM. same sites (T34, T67, Y103), carboxymethylation (K77, K78), 4-hydroxynonenal alkylation K78, K79) CONT VITE samples, indicating that these not influenced cattle. differential occurrence trimethylation samples. Overall, a greater number modified than VITE, suggesting decreased thenumbers post-translationally Additionally, at K87, K96, K98, K102 unique CONT, K118 VITE. These findings suggested cattle might protect acid Mb—especially those located spatially close proximal histidine—from undergoing PTM, thereby improving redox