Explaining meat quality of bulls and steers by differential proteome and phosphoproteome analysis of skeletal muscle

• Published in: Journal of proteomics Vol. 199; pp. 51 - 66
• Main Authors: Silva, Luiz H.P., Rodrigues, Rafael T.S., Assis, Débora E.F., Benedeti, Pedro D.B., Duarte, Marcio S., Chizzotti, Mario L.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.05.2019
• Subjects: Animals; Castration; Cattle; Glycolysis; Intramuscular fat; Male; Meat - standards; Meat aging; Muscle Proteins - metabolism; Muscle, Skeletal - chemistry; Muscle, Skeletal - enzymology; Muscle, Skeletal - metabolism; Phosphoprotein; Phosphoproteins - analysis; Phosphorylation; Proteome - analysis; Quality Control; Red Meat - analysis; Zebu cattle; Zebu cattle; Meat aging; Phosphoprotein; Castration; Intramuscular fat
• ISSN: 1874-3919; 1876-7737
• DOI: 10.1016/j.jprot.2019.03.004

The objective of this study was to evaluate the differential proteome and phosphoproteome between bulls and steers during conversion of muscle to meat, as well as after 14 days of aging. Twelve male Nellore (Bos taurus indicus) calves were used, and six calves were randomly selected for surgical castration. Calves were fed the same diet and were harvested after 230 days on feed. Longissimus muscle was sampled just after stunning (0d postmortem), at deboning (1d postmortem) and after aging (14d postmortem) for differential proteome analysis. Castration upregulated (P < 0.05) the abundance of glycolytic enzymes, while the oxidative phosphorylation protein ATP5B was downregulated (P < 0.05). In addition, abundance of troponin T fast isoform (TNNT3) was upregulated by castration (P < 0.05), while the slow isoform (TNNT1) tended to be decreased (P < 0.10). The creatine kinase M-type was markedly fragmented postmortem. Abundance of phosphorylated PGM1 increased during the first 24 h postmortem and was highly correlated with carcass pH. Further, abundance of the phosphorylated myofibrillar proteins ACTA1 and MYLPF were positively correlated with sarcomere shortening. Overall, our finds demonstrated that abundance and phosphorylation of glycolytic enzymes are associated with changes in beef tenderness and intramuscular fat. The design of the present study allowed to clarify the key proteins related to changes during conversion of muscle to meat such as pH decline and sarcomere shortening. In addition, the correlation between some biomarker and meat quality traits were confirmed. [Display omitted] •Steers had greater postmortem tenderization rate than bulls.•Castration shift muscle fiber toward fast-twitch and glycolytic metabolism.•Muscle abundance of glycolytic enzymes was correlated with intramuscular fat.•Phosphorylated phosphoglucomutase 1 abundance was correlated with fast pH decline.•The creatine kinase M-type was markedly fragmented postmortem.